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Sample records for gas treatment aplikasi

  1. Cryogenic treatment of gas

    SciTech Connect

    Bravo, Jose Luis; Harvey, III, Albert Destrehan; Vinegar, Harold J.

    2012-04-03

    Systems and methods of treating a gas stream are described. A method of treating a gas stream includes cryogenically separating a first gas stream to form a second gas stream and a third stream. The third stream is cryogenically contacted with a carbon dioxide stream to form a fourth and fifth stream. A majority of the second gas stream includes methane and/or molecular hydrogen. A majority of the third stream includes one or more carbon oxides, hydrocarbons having a carbon number of at least 2, one or more sulfur compounds, or mixtures thereof. A majority of the fourth stream includes one or more of the carbon oxides and hydrocarbons having a carbon number of at least 2. A majority of the fifth stream includes hydrocarbons having a carbon number of at least 3 and one or more of the sulfur compounds.

  2. Treatment of Gas

    MedlinePlus

    ... and how improve living with these conditions . Publication Library Books of Interest Medical Definitions About IFFGD About us Our Mission Awareness Activities Advocacy Activities Research Leadership IFFGD Symposium Report Industry Council Contact Us News Industry Treatment News Medical ...

  3. Flue gas desulfurization wastewater treatment primer

    SciTech Connect

    Higgins, T.E.; Sandy, A.T.; Givens, S.W.

    2009-03-15

    Purge water from a typical wet flue gas desulfurization system contains myriad chemical constituents and heavy metals whose mixture is determined by the fuel source and combustion products as well as the stack gas treatment process. A well-designed water treatment system can tolerate upstream fuel and sorbent arranged in just the right order to produce wastewater acceptable for discharge. This article presents state-of-the-art technologies for treating the waste water that is generated by wet FGD systems. 11 figs., 3 tabs.

  4. Endwall Treatment and Method for Gas Turbine

    NASA Technical Reports Server (NTRS)

    Hathaway, Michael D. (Inventor); Strazisar, Anthony J. (Inventor); Suder, Kenneth L. (Inventor)

    2006-01-01

    An endwall treatment for a gas turbine engine having at least one rotor blade extending from a rotatable hub and a casing circumferentially surrounding the rotor and the hub, the endwall treatment including, an inlet formed in an endwall of the gas turbine engine adapted to ingest fluid from a region of a higher-pressure fluid, an outlet formed in the endwall and located in a region of lower pressure than the inlet, wherein the inlet and the outlet are in a fluid communication with each other, the outlet being adapted to inject the fluid from the inlet in the region of lower pressure, and wherein the outlet is at least partially circumferentially offset relative to the inlet.

  5. Pathophysiology and treatment of decompression sickness and gas embolism.

    PubMed

    Loewenherz, J W

    1992-09-01

    Decompression sickness and cerebral gas embolism can present as dramatic and profound sudden onset injuries in patients engaged in tunnel work and compressed gas diving, including scuba. The history and management of these illnesses span centuries. The pathophysiology relates to occurrence of gas bubbles in extrapulmonic sites. Decompression sickness is due to supersaturation of the tissue with dissolved gas and subsequent evolution of gas bubbles. Gas embolism results from the direct transit of molecular gas from a pulmonary or intravascular origin into the arterial circulation causing occlusion of a distal locus. Treatment relates to increasing hydrostatic pressure, thus maximizing the gradient for gas reabsorption and dissolution and subsequently gas excretion via the lungs.

  6. Simultaneous stack-gas scrubbing and waste water treatment

    NASA Technical Reports Server (NTRS)

    Poradek, J. C.; Collins, D. D.

    1980-01-01

    Simultaneous treatment of wastewater and S02-laden stack gas make both treatments more efficient and economical. According to results of preliminary tests, solution generated by stack gas scrubbing cycle reduces bacterial content of wastewater. Both processess benefit by sharing concentrations of iron.

  7. Treatment of flue gas containing noxious gases

    SciTech Connect

    Dvirka, M.; Psihos, G.J.; Cosulich, J.J.

    1987-07-21

    A method is described of reducing the noxious gases such as chlorides including hydrogen chloride and chlorine from the flue gases derived from the incineration of solid waste materials in a furnace with a combustion chamber and a combustion zone to substantially reduce the formation of dioxins for a cleaner effluent gas to the atmosphere, comprising: introducing sodium bicarbonate into the flue gas of a furnace incinerating the waste materials, positioning introduction of sodium bicarbonate for at least one location along the path of the flue gas at a temperature below about 1564/sup 0/F but not below about 518/sup 0/F, heating the sodium bicarbonate in the flue gas for a time sufficient to drive off the water and carbon dioxide from the sodium bicarbonate, forming sodium carbonate particle during the heating of the sodium bicarbonate, the sodium carbonate having a higher porosity to produce a greater reaction area on the surface of the particles, contacting the porous sodium carbonate with chlorides in the flue gases for a sufficient time and temperature to react and produce sodium chloride and prevent their formation of dioxins; and separating the sodium chloride from the flue gas to produce a cleaner gas for exit to the atmosphere.

  8. New "wet type" electron beam flue gas treatment pilot plant

    NASA Astrophysics Data System (ADS)

    Tan, Erdal; Ünal, Suat; Doğan, Alişan; Letournel, Eric; Pellizzari, Fabien

    2016-02-01

    We describe a new pilot plant for flue gas cleaning by a high energy electron beam. The special feature of this pilot plant is a uniquely designed reactor called VGS® (VIVIRAD Gas Scrubber, patent pending), that allows oxidation/reduction treating flue gas in a single step. The VGS® process combines a scrubber and an advanced oxidation/reduction process with the objective of optimizing efficiency and treatment costs of flue gas purification by electron accelerators. Promising treatment efficiency was achieved for SOx and NOx removal in early tests (99.2% and 80.9% respectively). The effects of various operational parameters on treatment performance and by-product content were investigated during this study.

  9. Microwave off-gas treatment apparatus and process

    DOEpatents

    Schulz, Rebecca L.; Clark, David E.; Wicks, George G.

    2003-01-01

    The invention discloses a microwave off-gas system in which microwave energy is used to treat gaseous waste. A treatment chamber is used to remediate off-gases from an emission source by passing the off-gases through a susceptor matrix, the matrix being exposed to microwave radiation. The microwave radiation and elevated temperatures within the combustion chamber provide for significant reductions in the qualitative and quantitative emissions of the gas waste stream.

  10. Adsorption modeling for off-gas treatment

    SciTech Connect

    Ladshaw, A.; Sharma, K.; Yiacoumi, S.; Tsouris, C.; De Paoli, D.W.

    2013-07-01

    Off-gas generated from the reprocessing of used nuclear fuel contains a mixture of several radioactive gases including {sup 129}I{sub 2}, {sup 85}Kr, HTO, and {sup 14}CO{sub 2}. Over the past few decades, various separation and recovery processes have been studied for capturing these gases. Adsorption data for gaseous mixtures of species can be difficult to determine experimentally. Therefore, procedures capable of predicting the adsorption behavior of mixtures need to be developed from the individual isotherms of each of the pure species. A particular isotherm model of interest for the pure species is the Generalized Statistical Thermodynamic Adsorption isotherm. This model contains an adjustable number of parameters and will therefore describe a wide range of adsorption isotherms for a variety of components. A code has been developed in C++ to perform the non-linear regression analysis necessary for the determination of the isotherm parameters, as well as the least number of parameters needed to describe an entire set of data. (authors)

  11. Hyperbaric oxygen treatment for air or gas embolism.

    PubMed

    Moon, R E

    2014-01-01

    Gas can enter arteries (arterial gas embolism) due to alveolar-capillary disruption (caused by pulmonary overpressurization, e.g., breath-hold ascent by divers) or veins (venous gas embolism, VGE) as a result of tissue bubble formation due to decompression (diving, altitude exposure) or during certain surgical procedures where capillary hydrostatic pressure at the incision site is sub-atmospheric. Both AGE and VGE can be caused by iatrogenic gas injection. AGE usually produces strokelike manifestations, such as impaired consciousness, confusion, seizures and focal neurological deficits. Small amounts of VGE are often tolerated due to filtration by pulmonary capillaries. However, VGE can cause pulmonary edema, cardiac "vapor lock" and AGE due to transpulmonary passage or right-to-left shunt through a patent foramen ovale. Intravascular gas can cause arterial obstruction or endothelial damage and secondary vasospasm and capillary leak. Vascular gas is frequently not visible with radiographic imaging, which should not be used to exclude the diagnosis of AGE. Isolated VGE usually requires no treatment; AGE treatment is similar to decompression sickness (DCS), with first aid oxygen then hyperbaric oxygen. Although cerebral AGE (CAGE) often causes intracranial hypertension, animal studies have failed to demonstrate a benefit of induced hypocapnia. An evidence-based review of adjunctive therapies is presented.

  12. Sour gas injection for use with in situ heat treatment

    DOEpatents

    Fowler, Thomas David

    2009-11-03

    Systems, methods, and heaters for treating a subsurface formation are described herein. At least one method for providing acidic gas to a subsurface formation is described herein. The method may include providing heat from one or more heaters to a portion of a subsurface formation; producing fluids that include one or more acidic gases from the formation using a heat treatment process. At least a portion of one of the acidic gases may be introduced into the formation, or into another formation, through one or more wellbores at a pressure below a lithostatic pressure of the formation in which the acidic gas is introduced.

  13. Thermal treatment of soils contaminated with gas oil: influence of soil composition and treatment temperature.

    PubMed

    Piña, Juliana; Merino, Jerónimo; Errazu, Alberto F; Bucalá, Verónica

    2002-10-14

    Samples of two soils containing different organic matter contents, neat or contaminated with gas oil (diesel fuel oil) at 2.5 wt.% were heated from room temperature to different final temperatures (200-900 degrees C). The experiments, performed in an anaerobic media, simulate conditions pertinent to ex situ thermal desorptive and thermal destructive treatments. The products generated during the heating were collected and light gases were analyzed by gas chromatography. The results indicate that the chemical composition of the soil is a key factor since it strongly influences the quantity and composition of the off-gases. According to the liquid and light gas yields, the gas oil does not affect appreciably the generation of pyrolysis products of the own soil constituents and the gas oil does not suffer significant chemical transformations even at high operating temperatures (e.g. 900 degrees C). With surface areas of 16000 cm(2)/g (Soil A) and 85000 cm(2)/g (Soil B) based on the monolayer adsorbed model, 4 and 20%, respectively, of the original gas oil can be adsorbed. These values are in good agreement with experimental data. Even for high temperatures, the employed thermal treatment is capable to practically remove the gas oil from the soil bed without changing appreciably the original chemical composition of the contaminant.

  14. Greenhouse gas emissions from on-site wastewater treatment systems

    NASA Astrophysics Data System (ADS)

    Somlai-Haase, Celia; Knappe, Jan; Gill, Laurence

    2016-04-01

    Nearly one third of the Irish population relies on decentralized domestic wastewater treatment systems which involve the discharge of effluent into the soil via a percolation area (drain field). In such systems, wastewater from single households is initially treated on-site either by a septic tank and an additional packaged secondary treatment unit, in which the influent organic matter is converted into carbon dioxide (CO2) and methane (CH4) by microbial mediated processes. The effluent from the tanks is released into the soil for further treatment in the unsaturated zone where additional CO2 and CH4 are emitted to the atmosphere as well as nitrous oxide (N2O) from the partial denitrification of nitrate. Hence, considering the large number of on-site systems in Ireland and internationally, these are potential significant sources of greenhouse gas (GHG) emissions, and yet have received almost no direct field measurement. Here we present the first attempt to quantify and qualify the production and emissions of GHGs from a septic tank system serving a single house in the County Westmeath, Ireland. We have sampled the water for dissolved CO2, CH4 and N2O and measured the gas flux from the water surface in the septic tank. We have also carried out long-term flux measurements of CO2 from the drain field, using an automated soil gas flux system (LI-8100A, Li-Cor®) covering a whole year semi-continuously. This has enabled the CO2 emissions from the unsaturated zone to be correlated against different meteorological parameters over an annual cycle. In addition, we have integrated an ultraportable GHG analyser (UGGA, Los Gatos Research Inc.) into the automated soil gas flux system to measure CH4 flux. Further, manual sampling has also provided a better understanding of N2O emissions from the septic tank system.

  15. Initial table treatment of decompression sickness and arterial gas embolism.

    PubMed

    Bond, J G; Moon, R E; Morris, D L

    1990-08-01

    This descriptive, nonrandomized, multicenter-based study compares the treatment outcomes of two major categories of recompression treatment tables for recreational sport SCUBA divers suffering from decompression sickness and/or arterial gas embolism. Stratified and logistic regression analyses were used to compare the enhanced tables, which use pressures of 165 fsw (feet of salt water) or 60 fsw with extended recompression time, to the regular tables, which use pressures of 60 fsw or less without extended recompression time. A total of 113 cases were treated with enhanced tables, 54 being successes. A total of 214 cases were treated with regular tables, 135 being successes. The final logistic statistical model after adjusting for confounding factors found a significant improvement in successful treatment outcomes for divers treated with tables that use pressures of 60 fsw or less without extended recompression time (OR = 0.47, 95% CI = 0.28-0.78).

  16. FY-2001 Accomplishments in Off-gas Treatment Technology Development

    SciTech Connect

    Marshall, Douglas William

    2001-09-01

    This report summarizes the efforts funded by the Tank Focus Area to investigate nitrogen oxide (NOx) destruction (a.k.a. deNOx) technologies and off-gas scrubber system designs. The primary deNOx technologies that were considered are staged combustion (a.k.a. NOx reburning), selective catalytic reduction, selective non-catalytic reduction, and steam reformation. After engineering studies and a team evaluation were completed, selective catalytic reduction and staged combustion were considered the most likely candidate technologies to be deployed in a sodium-bearing waste vitrification facility. The outcome of the team evaluation factored heavily in the establishing a baseline configuration for off-gas and secondary waste treatment systems.

  17. Optimization of wastewater treatment plant operation for greenhouse gas mitigation.

    PubMed

    Kim, Dongwook; Bowen, James D; Ozelkan, Ertunga C

    2015-11-01

    This study deals with the determination of optimal operation of a wastewater treatment system for minimizing greenhouse gas emissions, operating costs, and pollution loads in the effluent. To do this, an integrated performance index that includes three objectives was established to assess system performance. The ASMN_G model was used to perform system optimization aimed at determining a set of operational parameters that can satisfy three different objectives. The complex nonlinear optimization problem was simulated using the Nelder-Mead Simplex optimization algorithm. A sensitivity analysis was performed to identify influential operational parameters on system performance. The results obtained from the optimization simulations for six scenarios demonstrated that there are apparent trade-offs among the three conflicting objectives. The best optimized system simultaneously reduced greenhouse gas emissions by 31%, reduced operating cost by 11%, and improved effluent quality by 2% compared to the base case operation.

  18. Neural network models for biological waste-gas treatment systems.

    PubMed

    Rene, Eldon R; Estefanía López, M; Veiga, María C; Kennes, Christian

    2011-12-15

    This paper outlines the procedure for developing artificial neural network (ANN) based models for three bioreactor configurations used for waste-gas treatment. The three bioreactor configurations chosen for this modelling work were: biofilter (BF), continuous stirred tank bioreactor (CSTB) and monolith bioreactor (MB). Using styrene as the model pollutant, this paper also serves as a general database of information pertaining to the bioreactor operation and important factors affecting gas-phase styrene removal in these biological systems. Biological waste-gas treatment systems are considered to be both advantageous and economically effective in treating a stream of polluted air containing low to moderate concentrations of the target contaminant, over a rather wide range of gas-flow rates. The bioreactors were inoculated with the fungus Sporothrix variecibatus, and their performances were evaluated at different empty bed residence times (EBRT), and at different inlet styrene concentrations (C(i)). The experimental data from these bioreactors were modelled to predict the bioreactors performance in terms of their removal efficiency (RE, %), by adequate training and testing of a three-layered back propagation neural network (input layer-hidden layer-output layer). Two models (BIOF1 and BIOF2) were developed for the BF with different combinations of easily measurable BF parameters as the inputs, that is concentration (gm(-3)), unit flow (h(-1)) and pressure drop (cm of H(2)O). The model developed for the CSTB used two inputs (concentration and unit flow), while the model for the MB had three inputs (concentration, G/L (gas/liquid) ratio, and pressure drop). Sensitivity analysis in the form of absolute average sensitivity (AAS) was performed for all the developed ANN models to ascertain the importance of the different input parameters, and to assess their direct effect on the bioreactors performance. The performance of the models was estimated by the regression

  19. Nutrient removal and greenhouse gas emissions in duckweed treatment ponds.

    PubMed

    Sims, Atreyee; Gajaraj, Shashikanth; Hu, Zhiqiang

    2013-03-01

    Stormwater treatment ponds provide a variety of functions including sediment retention, organic and nutrient removal, and habitat restoration. The treatment ponds are, however, also a source of greenhouse gases. The objectives of this study were to assess greenhouse gas (CH(4), CO(2) and N(2)O) emissions in duckweed treatment ponds (DWPs) treating simulated stormwater and to determine the role of ammonia-oxidizing organisms in nutrient removal and methanogens in greenhouse gas emissions. Two replicated DWPs operated at a hydraulic retention time (HRT) of 10 days were able to remove 84% (± 4% [standard deviation]) chemical oxygen demand (COD), 79% (± 3%) NH(4)(+)-N, 86% (± 2%) NO(3)(-)-N and 56% (± 7%) orthophosphate. CH(4) emission rates in the DWPs ranged from 502 to 1900 mg CH(4) m(-2) d(-1) while those of nitrous oxide (N(2)O) ranged from 0.63 to 4 mg N(2)O m(-2) d(-1). The CO(2) emission rates ranged from 1700 to 3300 mg CO(2) m(-2) day(-1). Duckweed coverage on water surface along with the continued deposit of duckweed debris in the DWPs and low-nutrient influent water created a low dissolved oxygen environment for the growth of unique ammonia-oxidizing organisms and methanogens. Archaeal and bacterial amoA abundance in the DWPs ranged from (1.5 ± 0.2) × 10(7) to (1.7 ± 0.2) × 10(8) copies/g dry soil and from (1.0 ± 0.3) × 10(3) to (1.5 ± 0.4) × 10(6) copies/g dry soil, respectively. The 16S rRNA acetoclastic and hydrogenotrophic methanogens ranged from (5.2 ± 0.2) × 10(5) to (9.0 ± 0.3) × 10(6) copies/g dry soil and from (1.0 ± 0.1) × 10(2) to (5.5 ± 0.4) × 10(3) copies/g dry soil, respectively. Ammonia-oxidizing archaea (AOA) appeared to be the dominant nitrifiers and acetoclastic Methanosaeta was the major methanogenic genus. The results suggest that methane is the predominant (>90%) greenhouse gas in the DWPs, where the relatively low stormwater nutrient inputs facilitate the growth of K-strategists such as AOA and Methanosaeta that may

  20. Quantification of greenhouse gas emissions from sludge treatment wetlands.

    PubMed

    Uggetti, Enrica; García, Joan; Lind, Saara E; Martikainen, Pertti J; Ferrer, Ivet

    2012-04-15

    Constructed wetlands are nowadays successfully employed as an alternative technology for wastewater and sewage sludge treatment. In these systems organic matter and nutrients are transformed and removed by a variety of microbial reaction and gaseous compounds such as methane (CH(4)) and nitrous oxide (N(2)O) may be released to the atmosphere. The aim of this work is to introduce a method to determine greenhouse gas emissions from sludge treatment wetlands (STW) and use the method in a full-scale system. Sampling and analysing techniques used to determine greenhouse gas emissions from croplands and natural wetlands were successfully adapted to the quantification of CH(4) and N(2)O emissions from an STW. Gas emissions were measured using the static chamber technique in 9 points of the STW during 13 days. The spatial variation in the emission along the wetland did not follow some specific pattern found for the temporal variation in the fluxes. Emissions ranged from 10 to 5400 mg CH(4)/m(2)d and from 20 to 950 mgN(2)O/m(2)d, depending on the feeding events. The comparison between the CH(4) and N(2)O emissions of different sludge management options shows that STW have the lowest atmospheric impact in terms of CO(2) equivalent emissions (Global warming potential with time horizon of 100 years): 17 kg CO(2) eq/PE y for STW, 36 kg CO(2) eq/PE y for centrifuge and 162 kg CO(2) eq/PE y for untreated sludge transport, PE means Population Equivalent.

  1. Greenhouse gas emissions from sludge treatment reed beds.

    PubMed

    Cui, Yubo; Zhang, Shunli; Chen, Zhaobo; Chen, Rui; Deng, Xinnan

    2015-01-01

    Sludge treatment reed bed systems (STRBs) are considered as an alternative technology for surplus sludge treatment. Organic matter is decomposed by various microbial reactions, resulting in gases such as CO₂and CH₄emitting into the atmosphere. The aim of this study is to investigate gas emission from STRBs. The static transparent chamber was adopted to measure gas emission; it allows sunlight to enter and plants to photosynthesise. The comparison of total solids and volatile solids showed STRBs have a higher efficiency in dewatering and mineralization than a conventional unplanted sludge drying bed (USDB). The CO₂emission ranged from 28.68 to 100.42 g CO₂m⁻² d(-1) in USDB, from 16.48 to 65.18 g CO₂m⁻² d⁻¹ in STRBs; CH₄emission ranged from 0.26 to 0.99 g CH₄ m⁻² d⁻¹ in USDB, from 0.43 to 1.95 g CH₄m⁻² d⁻¹ in STRBs. Both gas fluxes decreased towards the end of vegetation and reached the highest rates during the hot and dry summer. After the system was loaded by sludge, the fluxes of CO₂and CH₄significantly decreased in the USDB, whereas they increased in STRBs. In terms of CO₂equivalent, the global warming potential of CH₄was 13.13 g CO₂eq m⁻² d⁻¹ and 15.02 g CO₂eq m⁻² d⁻¹ in USDB and STRBs, respectively.

  2. Green house gas emissions from composting and mechanical biological treatment.

    PubMed

    Amlinger, Florian; Peyr, Stefan; Cuhls, Carsten

    2008-02-01

    In order to carry out life-cycle assessments as a basis for far-reaching decisions about environmentally sustainable waste treatment, it is important that the input data be reliable and sound. A comparison of the potential greenhouse gas (GHG) emissions associated with each solid waste treatment option is essential. This paper addresses GHG emissions from controlled composting processes. Some important methodological prerequisites for proper measurement and data interpretation are described, and a common scale and dimension of emission data are proposed so that data from different studies can be compared. A range of emission factors associated with home composting, open windrow composting, encapsulated composting systems with waste air treatment and mechanical biological waste treatment (MBT) are presented from our own investigations as well as from the literature. The composition of source materials along with process management issues such as aeration, mechanical agitation, moisture control and temperature regime are the most important factors controlling methane (CH4), nitrous oxide (N2O) and ammoniac (NH3) emissions. If ammoniac is not stripped during the initial rotting phase or eliminated by acid scrubber systems, biofiltration of waste air provides only limited GHG mitigation, since additional N2O may be synthesized during the oxidation of NH3, and only a small amount of CH4 degradation occurs in the biofilter. It is estimated that composting contributes very little to national GHG inventories generating only 0.01-0.06% of global emissions. This analysis does not include emissions from preceding or post-treatment activities (such as collection, transport, energy consumption during processing and land spreading), so that for a full emissions account, emissions from these activities would need to be added to an analysis.

  3. Green house gas emissions from composting and mechanical biological treatment.

    PubMed

    Amlinger, Florian; Peyr, Stefan; Cuhls, Carsten

    2008-02-01

    In order to carry out life-cycle assessments as a basis for far-reaching decisions about environmentally sustainable waste treatment, it is important that the input data be reliable and sound. A comparison of the potential greenhouse gas (GHG) emissions associated with each solid waste treatment option is essential. This paper addresses GHG emissions from controlled composting processes. Some important methodological prerequisites for proper measurement and data interpretation are described, and a common scale and dimension of emission data are proposed so that data from different studies can be compared. A range of emission factors associated with home composting, open windrow composting, encapsulated composting systems with waste air treatment and mechanical biological waste treatment (MBT) are presented from our own investigations as well as from the literature. The composition of source materials along with process management issues such as aeration, mechanical agitation, moisture control and temperature regime are the most important factors controlling methane (CH4), nitrous oxide (N2O) and ammoniac (NH3) emissions. If ammoniac is not stripped during the initial rotting phase or eliminated by acid scrubber systems, biofiltration of waste air provides only limited GHG mitigation, since additional N2O may be synthesized during the oxidation of NH3, and only a small amount of CH4 degradation occurs in the biofilter. It is estimated that composting contributes very little to national GHG inventories generating only 0.01-0.06% of global emissions. This analysis does not include emissions from preceding or post-treatment activities (such as collection, transport, energy consumption during processing and land spreading), so that for a full emissions account, emissions from these activities would need to be added to an analysis. PMID:18338701

  4. Electron beam treatment of exhaust gas with high NOx concentration

    NASA Astrophysics Data System (ADS)

    Licki, Janusz; Chmielewski, Andrzej G.; Pawelec, Andrzej; Zimek, Zbigniew; Witman, Sylwia

    2014-05-01

    Simulated exhaust gases with a high NOx concentration, ranging from 200 to 1700 ppmv, were irradiated by an electron beam from an accelerator. In the first part of this study, only exhaust gases were treated. Low NOx removal efficiencies were obtained for high NOx concentrations, even with high irradiation doses applied. In the second part of study, gaseous ammonia or/and vapor ethanol were added to the exhaust gas before its inlet to the plasma reactor. These additions significantly enhanced the NOx removal efficiency. The synergistic effect of high SO2 concentration on NOx removal was observed. The combination of electron beam treatment with the introduction of the above additions and with the performance of irradiation under optimal parameters ensured high NOx removal efficiency without the application of a solid-state catalyst.

  5. Treatment of gas from an in situ conversion process

    SciTech Connect

    Diaz, Zaida; Del Paggio, Alan Anthony; Nair, Vijay; Roes, Augustinus Wilhelmus Maria

    2011-12-06

    A method of producing methane is described. The method includes providing formation fluid from a subsurface in situ conversion process. The formation fluid is separated to produce a liquid stream and a first gas stream. The first gas stream includes olefins. At least the olefins in the first gas stream are contacted with a hydrogen source in the presence of one or more catalysts and steam to produce a second gas stream. The second gas stream is contacted with a hydrogen source in the presence of one or more additional catalysts to produce a third gas stream. The third gas stream includes methane.

  6. Sorption Modeling and Verification for Off-Gas Treatment

    SciTech Connect

    Tavlarides, Lawrence L.; Lin, Ronghong; Nan, Yue; Yiacoumi, Sotira; Tsouris, Costas; Ladshaw, Austin; Sharma, Ketki; Gabitto, Jorge; DePaoli, David

    2015-04-29

    The project has made progress toward developing a comprehensive modeling capability for the capture of target species in off gas evolved during the reprocessing of nuclear fuel. The effort has integrated experimentation, model development, and computer code development for adsorption and absorption processes. For adsorption, a modeling library has been initiated to include (a) equilibrium models for uptake of off-gas components by adsorbents, (b) mass transfer models to describe mass transfer to a particle, diffusion through the pores of the particle and adsorption on the active sites of the particle, and (c) interconnection of these models to fixed bed adsorption modeling which includes advection through the bed. For single-component equilibria, a Generalized Statistical Thermodynamic Adsorption (GSTA) code was developed to represent experimental data from a broad range of isotherm types; this is equivalent to a Langmuir isotherm in the two-parameter case, and was demonstrated for Kr on INL-engineered sorbent HZ PAN, water sorption on molecular sieve A sorbent material (MS3A), and Kr and Xe capture on metal-organic framework (MOF) materials. The GSTA isotherm was extended to multicomponent systems through application of a modified spreading pressure surface activity model and generalized predictive adsorbed solution theory; the result is the capability to estimate multicomponent adsorption equilibria from single-component isotherms. This advance, which enhances the capability to simulate systems related to off-gas treatment, has been demonstrated for a range of real-gas systems in the literature and is ready for testing with data currently being collected for multicomponent systems of interest, including iodine and water on MS3A. A diffusion kinetic model for sorbent pellets involving pore and surface diffusion as well as external mass transfer has been established, and a methodology was developed for determining unknown diffusivity parameters from transient

  7. Greenhouse gas emissions from municipal wastewater treatment plants

    NASA Astrophysics Data System (ADS)

    Parravicini, Vanessa; Svardal, Karl

    2016-04-01

    Operating wastewater treatment plants (WWTP) represent a source of greenhouse gases (GHG). Direct GHG emissions include emissions of methane (CH4) and nitrous oxide (N2O) that can be biologically produced during wastewater and sewage sludge treatment. This is also highlighted in the Intergovernmental Panel on Climate Change (IPCC 2006) guidelines used for national GHG inventories. Indirect GHG emissions occur at WWTPs mainly by the consumption of electricity, fossil fuel for transportation and by the use of chemicals (e.g. coagulants). In this study, the impact of direct and indirect GHG emissions was quantified for two model WWTPs of 50.000 person equivalents (p.e.) using carbon footprint analyses. It was assumed that at one WWTP sewage sludge is digested anaerobically, at the other one it is aerobically stabilised in the activated sludge tank. The carbon footprint analyses were performed using literature emission factors. A new estimation model based on measurements at eight Austrian WWTPs was used for the assessment of N2O direct emissions (Parravicini et al., 2015). The results of the calculations show that, under the selected assumptions, the direct N2O emission from the activated sludge tank can dominate the carbon footprint of WWTP with a poor nitrogen removal efficiency. Through an improved operation of nitrogen removal several advantages can be gained: direct N2O emissions can be reduced, the energy demand for aeration can be decreased and a higher effluent quality can be achieved. Anaerobic digesters and anaerobic sludge storage tanks can become a relevant source of direct CH4 emissions. Minimising of CH4 losses from these sources improves the carbon footprint of the WWTP also increasing the energy yield achievable by combusting this renewable energy carrier in a combined heat and power unit. The estimated carbon footprint of the model WWTPs lies between 20 and 40 kg CO2e/p.e./a. This corresponds to 0.2 to 0.4% of the CO2e average emission caused yearly

  8. Forming gas treatment of lithium ion battery anode graphite powders

    DOEpatents

    Contescu, Cristian Ion; Gallego, Nidia C; Howe, Jane Y; Meyer, III, Harry M; Payzant, Edward Andrew; Wood, III, David L; Yoon, Sang Young

    2014-09-16

    The invention provides a method of making a battery anode in which a quantity of graphite powder is provided. The temperature of the graphite powder is raised from a starting temperature to a first temperature between 1000 and 2000.degree. C. during a first heating period. The graphite powder is then cooled to a final temperature during a cool down period. The graphite powder is contacted with a forming gas during at least one of the first heating period and the cool down period. The forming gas includes H.sub.2 and an inert gas.

  9. Removal and treatment of mercury contamination at gas processing facilities

    SciTech Connect

    Wilhelm, S.M.; McArthur, A.

    1995-12-01

    Processing of gas containing mercury invariably leads to contamination of equipment and can generate waste in the form of sludge and spent adsorbent materials. Occasional accidents can also lead to soil contamination. This paper reviews mercury contamination in the gas processing industry and discusses newly developed methods for clean-up and disposal of mercury waste. Research and development (sponsored by the Gas Research Institute) have produced new technology for mercury removal from complex matrices. Equipment decontamination is accomplished using chemical cleaning solutions that selectively oxidize and complex elemental mercury deposits. These cleaning formulations include aqueous base solutions containing iodine as the completing agent and organic (alcohol) base solutions using completing agents. Soil, sludge, and debris must be thermally processed to remove (recycle) mercury. Thermal systems use vacuum, inert gas, or air as the carder medium. If air is used, sulfur in the matrix is converted to SO{sub 2} and hydrocarbons are oxidized as well, depending upon design. Anaerobic thermal systems employ selective condensation and/or adsorption to separate sulfur and hydrocarbons from mercury. Spent adsorbent materials are also thermally processed using strictly anaerobic conditions to avoid exothermal reactions involving carbon. The regulatory climate relative to mercury is changing rapidly. Regulations covering treated debris and soils may require total mercury concentrations of less than 2 mg/kg for burial. Total mercury analysis rather than leaching procedure (TCLP) is becoming the norm in regulations and specifications. Sampling and analysis procedures for contaminated surfaces are under development.

  10. Upgrading producer gas quality from rubber wood gasification in a radio frequency tar thermocatalytic treatment reactor.

    PubMed

    Anis, Samsudin; Zainal, Z A

    2013-12-01

    This study focused on improving the producer gas quality using radio frequency (RF) tar thermocatalytic treatment reactor. The producer gas containing tar, particles and water was directly passed at a particular flow rate into the RF reactor at various temperatures for catalytic and thermal treatments. Thermal treatment generates higher heating value of 5.76 MJ Nm(-3) at 1200°C. Catalytic treatments using both dolomite and Y-zeolite provide high tar and particles conversion efficiencies of about 97% on average. The result also showed that light poly-aromatic hydrocarbons especially naphthalene and aromatic compounds particularly benzene and toluene were still found even at higher reaction temperatures. Low energy intensive RF tar thermocatalytic treatment was found to be effective for upgrading the producer gas quality to meet the end user requirements and increasing its energy content.

  11. Upgrading producer gas quality from rubber wood gasification in a radio frequency tar thermocatalytic treatment reactor.

    PubMed

    Anis, Samsudin; Zainal, Z A

    2013-12-01

    This study focused on improving the producer gas quality using radio frequency (RF) tar thermocatalytic treatment reactor. The producer gas containing tar, particles and water was directly passed at a particular flow rate into the RF reactor at various temperatures for catalytic and thermal treatments. Thermal treatment generates higher heating value of 5.76 MJ Nm(-3) at 1200°C. Catalytic treatments using both dolomite and Y-zeolite provide high tar and particles conversion efficiencies of about 97% on average. The result also showed that light poly-aromatic hydrocarbons especially naphthalene and aromatic compounds particularly benzene and toluene were still found even at higher reaction temperatures. Low energy intensive RF tar thermocatalytic treatment was found to be effective for upgrading the producer gas quality to meet the end user requirements and increasing its energy content. PMID:24185417

  12. BUNCOMBE COUNTY WASTEWATER PRE-TREATMENT AND LANDFILL GAS TO ENERGY PROJECT

    SciTech Connect

    Jon Creighton

    2012-03-13

    The objective of this project was to construct a landfill gas-to-energy (LFGTE) facility that generates a renewable energy source utilizing landfill gas to power a 1.4MW generator, while at the same time reducing the amount of leachate hauled offsite for treatment. The project included an enhanced gas collection and control system, gas conditioning equipment, and a 1.4 MW generator set. The production of cleaner renewable energy will help offset the carbon footprint of other energy sources that are currently utilized.

  13. Gas treatment and by-products recovery of Thailand`s first coke plant

    SciTech Connect

    Diemer, P.E.; Seyfferth, W.

    1997-12-31

    Coke is needed in the blast furnace as the main fuel and chemical reactant and the main product of a coke plant. The second main product of the coke plant is coke oven gas. During treatment of the coke oven gas some coal chemicals like tar, ammonia, sulphur and benzole can be recovered as by-products. Since the market prices for these by-products are rather low and often erratic it does not in most cases justify the investment to recover these products. This is the reason why modern gas treatment plants only remove those impurities from the crude gas which must be removed for technical and environmental reasons. The cleaned gas, however, is a very valuable product as it replaces natural gas in steel work furnaces and can be used by other consumers. The surplus can be combusted in the boiler of a power plant. A good example for an optimal plant layout is the new coke oven facility of Thai Special Steel Industry (TSSI) in Rayong. The paper describes the TSSI`s coke oven gas treatment plant.

  14. Treatment of Dye Wastewater by Using a Hybrid Gas/Liquid Pulsed Discharge Plasma Reactor

    NASA Astrophysics Data System (ADS)

    Lu, Na; Li, Jie; Wu, Yan; Masayuki, Sato

    2012-02-01

    A hybrid gas/liquid pulsed discharge plasma reactor using a porous ceramic tube is proposed for dye wastewater treatment. High voltage pulsed discharge plasma was generated in the gas phase and simultaneously the plasma channel was permeated through the tiny holes of the ceramic tube into the water phase accompanied by gas bubbles. The porous ceramic tube not only separated the gas phase and liquid phase but also offered an effective plasma spreading channel. The effects of the peak pulse voltage, additive gas varieties, gas bubbling rate, solution conductivity and TiO2 addition were investigated. The results showed that this reactor was effective for dye wastewater treatment. The decoloration efficiency of Acid Orange II was enhanced with an increase in the power supplied. Under the studied conditions, 97% of Acid Orange II in aqueous solution was effectively decolored with additive oxygen gas, which was 51% higher than that with argon gas, and the increasing O2 bubbling rate also benefited the decoloration of dye wastewater. Water conductivity had a small effect on the level of decoloration. Catalysis of TiO2 could be induced by the pulsed discharge plasma and addition of TiO2 aided the decoloration of Acid Orange II.

  15. Selection among aqueous and off-gas treatment technologies for synthetic organic chemicals

    SciTech Connect

    Dvorak, B.I.; Herbeck, C.J.; Meurer, C.P.; Lawler, D.F.; Speitel, G.E. Jr.

    1996-07-01

    A methodology for selecting the least-cost treatment technology for waters contaminated by organic wastes was developed using performance and cost models. This methodology simplifies the selection of the least expensive treatment process(es) for a given set of conditions. Two aqueous-phase treatment options were considered: air stripping and liquid-phase adsorption (granular activated carbon). When the off-gases from air stripping must be treated, four off-gas treatment options were considered: gas-phase adsorption (with both on- and off-site regeneration of the granular activated carbon), thermal incineration, and catalytic oxidation. Methodologies were developed for rapidly selecting the least-cost off-gas treatment option [for volatile organic compound (VOC) sources such as an air stripping tower], for selecting the least-cost overall (liquid and gas phase treatment) system, and for selecting the least-cost overall system for a multicomponent mixture. The comparison methodology is based on physical parameters of the target chemical: Henry`s constant and the solute distribution parameter. The results are a set of diagrams and heuristics for rapid identification of cases for which one treatment option is significantly less expensive than the other.

  16. Greenhouse Gas Emissions From Urban Wastewater Treatment Plants

    NASA Astrophysics Data System (ADS)

    Sturchio, N. C.; Bellucci, F.; Gonzalez-Meler, M. A.; Heraty, L.; Kozak, J. A.

    2010-12-01

    Wastewater treatment plants are considered the seventh highest contributor of greenhouse gases (GHG) to the atmosphere. For instance, USEPA recently reported (http://epa.gov/climatechange/emissions/downloads10/US-GHG-Inventory-2010_Chapter8-Waste.pdf) that U.S. wastewater treatment released 24.3 Tg CO2e (i.e. CO2 GHG equivalents) via CH4 and 4.9 Tg CO2e via N20 during 2008. Emissions of GHG from wastewater treatment sources are often modeled using algorithms that rely on surrogates such as five-day Biological or Chemical Oxygen Demand [B(C)OD5] for CH4 and protein content of diets for N2O. Unfortunately, empirical validation of these models using field data is lacking. To fill this gap, we measured annual CH4 and N20 emissions from three wastewater treatment plants in the Chicago region that differ in size and design. Plants ranged from serving 0.17 to 2.3 million people, treating from 27 to 751 millions of gallons of wastewater per day, and having BOD5 from 101 to 220 mg/L. Primary settling tanks, exhausts, and aeration basins were the main sources of CH4 emissions, whereas N2O was mainly emitted by aeration basins at the three plants investigated. During 2009, per capita emissions for CH4 and N2O (for every thousand people) ranged from 61 to 1130 kg/yr and from 12 to 226 Kg/yr, respectively. These wide variations were in part due to chemistry of influent waters and plant design. We found that IPCC and USEPA algorithms were good predictors of CH4 emissions but they largely underestimated N20 emissions. Despite the differences in plant design and per capita emissions, we found that all three plants have a similar CH4:N2O flux ratio. If this flux ratio proves to be a general characteristic of wastewater treatment plants, it could provide a more accurate alternative to current models for estimation of N2O emissions.

  17. A rational procedure for estimation of greenhouse-gas emissions from municipal wastewater treatment plants.

    PubMed

    Monteith, Hugh D; Sahely, Halla R; MacLean, Heather L; Bagley, David M

    2005-01-01

    Municipal wastewater treatment may lead to the emission of greenhouse gases. The current Intergovenmental Panel on Climate Change (Geneva, Switzerland) approach attributes only methane emissions to wastewater treatment, but this approach may overestimate greenhouse gas emissions from the highly aerobic processes primarily used in North America. To better estimate greenhouse gas emissions, a procedure is developed that can be used either with plant-specific data or more general regional data. The procedure was evaluated using full-scale data from 16 Canadian wastewater treatment facilities and then applied to all 10 Canadian provinces. The principal greenhouse gas emitted from municipal wastewater treatment plants was estimated to be carbon dioxide (CO2), with very little methane expected. The emission rates ranged from 0.005 kg CO2-equivalent/m3 treated for primary treatment facilities to 0.26 kg CO2-equivalent/m3 for conventional activated sludge, with anaerobic sludge digestion to over 0.8 kg CO2-equivalent/m3 for extended aeration with aerobic digestion. Increasing the effectiveness of biogas generation and use will decrease the greenhouse gas emissions that may be assigned to the wastewater treatment plant.

  18. An investigation of gas separation membranes for reduction of thermal treatment emissions

    SciTech Connect

    Stull, D.M.; Logsdon, B.W.; Pellegrino, J.J.

    1994-05-16

    Gas permeable membranes were evaluated for possible use as air pollution control devices on a fluidized bed catalytic incineration unit. The unit is a candidate technology for treatment of certain mixed hazardous and radioactive wastes at the Rocky Flats Plant. Cellulose acetate and polyimide membranes were tested to determine the permeance of typical off-gas components such as carbon dioxide, nitrogen, and oxygen. Multi-component permeation studies included gas mixtures containing light hydrocarbons. Experiments were also conducted to discover information about potential membrane degradation in the presence of organic compounds.

  19. Characterization of oil and gas waste disposal practices and assessment of treatment costs. Final report

    SciTech Connect

    Bedient, P.B.

    1995-01-16

    This study examines wastes associated with the onshore exploration and production of crude oil and natural gas in the US. The objective of this study was to update and enhance the current state of knowledge with regard to oil and gas waste quantities, the potential environmental impact of these wastes, potential methods of treatment, and the costs associated with meeting various degrees of treatment. To meet this objective, the study consisted of three tasks: (1) the development of a production Environmental Database (PED) for the purpose of assessing current oil and gas waste volumes by state and for investigating the potential environmental impacts associated with current waste disposal practices on a local scale; (2) the evaluation of available and developing technologies for treating produced water waste streams and the identification of unit process configurations; and (3) the evaluation of the costs associated with various degrees of treatment achievable by different treatment configurations. The evaluation of feasible technologies for the treatment of produced water waste streams was handled in the context of comparing the level of treatment achievable with the associated cost of treatment. Treatment processes were evaluated for the removal of four categories of produced water contaminants: particulate material, volatile organic compounds, adsorbable organic compounds, and dissolved inorganic species. Results showed dissolved inorganic species to be the most costly to remove. The potential cost of treating all 18.3 billion barrels of produced water generated in a year amounts to some 15 billion dollars annually.

  20. Advanced Off-Gas Control System Design For Radioactive And Mixed Waste Treatment

    SciTech Connect

    Nick Soelberg

    2005-09-01

    Treatment of radioactive and mixed wastes is often required to destroy or immobilize hazardous constituents, reduce waste volume, and convert the waste to a form suitable for final disposal. These kinds of treatments usually evolve off-gas. Air emission regulations have become increasingly stringent in recent years. Mixed waste thermal treatment in the United States is now generally regulated under the Hazardous Waste Combustor (HWC) Maximum Achievable Control Technology (MACT) standards. These standards impose unprecedented requirements for operation, monitoring and control, and emissions control. Off-gas control technologies and system designs that were satisfactorily proven in mixed waste operation prior to the implementation of new regulatory standards are in some cases no longer suitable in new mixed waste treatment system designs. Some mixed waste treatment facilities have been shut down rather than have excessively restrictive feed rate limits or facility upgrades to comply with the new standards. New mixed waste treatment facilities in the U. S. are being designed to operate in compliance with the HWC MACT standards. Activities have been underway for the past 10 years at the INL and elsewhere to identify, develop, demonstrate, and design technologies for enabling HWC MACT compliance for mixed waste treatment facilities. Some specific off-gas control technologies and system designs have been identified and tested to show that even the stringent HWC MACT standards can be met, while minimizing treatment facility size and cost.

  1. Design and Implementation of Energized Fracture Treatment in Tight Gas Sands

    SciTech Connect

    Mukul Sharma; Kyle Friehauf

    2009-12-31

    Hydraulic fracturing is essential for producing gas and oil at an economic rate from low permeability sands. Most fracturing treatments use water and polymers with a gelling agent as a fracturing fluid. The water is held in the small pore spaces by capillary pressure and is not recovered when drawdown pressures are low. The un-recovered water leaves a water saturated zone around the fracture face that stops the flow of gas into the fracture. This is a particularly acute problem in low permeability formations where capillary pressures are high. Depletion (lower reservoir pressures) causes a limitation on the drawdown pressure that can be applied. A hydraulic fracturing process can be energized by the addition of a compressible, sometimes soluble, gas phase into the treatment fluid. When the well is produced, the energized fluid expands and gas comes out of solution. Energizing the fluid creates high gas saturation in the invaded zone, thereby facilitating gas flowback. A new compositional hydraulic fracturing model has been created (EFRAC). This is the first model to include changes in composition, temperature, and phase behavior of the fluid inside the fracture. An equation of state is used to evaluate the phase behavior of the fluid. These compositional effects are coupled with the fluid rheology, proppant transport, and mechanics of fracture growth to create a general model for fracture creation when energized fluids are used. In addition to the fracture propagation model, we have also introduced another new model for hydraulically fractured well productivity. This is the first and only model that takes into account both finite fracture conductivity and damage in the invaded zone in a simple analytical way. EFRAC was successfully used to simulate several fracture treatments in a gas field in South Texas. Based on production estimates, energized fluids may be required when drawdown pressures are smaller than the capillary forces in the formation. For this field

  2. Enhancement of methane gas sensing characteristics of graphene oxide sensor by heat treatment and laser irradiation.

    PubMed

    Assar, Mohammadreza; Karimzadeh, Rouhollah

    2016-12-01

    The present study uses a rapid, easy and practical method for cost-effective fabrication of a methane gas sensor. The sensor was made by drop-casting a graphene oxide suspension onto an interdigital circuit surface. The electrical conductivity and gas-sensing characteristics of the sensor were determined and then heat treatment and in situ laser irradiation were applied to improve the device conductivity and gas sensitivity. Real-time monitoring of the evolution of the device current as a function of heat treatment time revealed significant changes in the conductance of the graphene oxide sensor. The use of low power laser irradiation enhanced both the electrical conductivity and sensing response of the graphene oxide sensor.

  3. Enhancement of methane gas sensing characteristics of graphene oxide sensor by heat treatment and laser irradiation.

    PubMed

    Assar, Mohammadreza; Karimzadeh, Rouhollah

    2016-12-01

    The present study uses a rapid, easy and practical method for cost-effective fabrication of a methane gas sensor. The sensor was made by drop-casting a graphene oxide suspension onto an interdigital circuit surface. The electrical conductivity and gas-sensing characteristics of the sensor were determined and then heat treatment and in situ laser irradiation were applied to improve the device conductivity and gas sensitivity. Real-time monitoring of the evolution of the device current as a function of heat treatment time revealed significant changes in the conductance of the graphene oxide sensor. The use of low power laser irradiation enhanced both the electrical conductivity and sensing response of the graphene oxide sensor. PMID:27567028

  4. Validity of using backward Lagrangian Stochastic technique in measuring trace gas emission from treatment lagoon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study evaluates the accuracy of measuring trace gas emission from treatment lagoons using backward Lagrangian stochastic (bLs) technique. The bLs technique was originally developed for relatively homogeneous terrains without any obstacles causing significant windflow disturbance. The errors ass...

  5. FIELD MEASUREMENT OF GREENHOUSE GAS EMISSION RATES AND DEVELOPMENT OF EMISSION FACTORS FOR WASTEWATER TREATMENT

    EPA Science Inventory

    The report gives results of field testing to develop more reliable green house gas (GHG) emission estimates for Wastewater treatment (WWT) lagoons. (NOTE: Estimates are available for the amount of methane (CH4) emitted from certain types of waste facilities, but there is not adeq...

  6. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-08-01

    Gas-Gun treatments. (2) Results indicate that the candidate selection methodology was marginally successful based on the pressure transient test results, but highly successful based on the workovers. For the selected candidate wells that were worked over, incremental reserve costs were < $ 0.10/Mcf. For the non-candidates, incremental reserve costs were {+-} > $1.00/Mcf. (3) Based on the combined results, the accuracy of the candidate selection methodology tested under this project is unclear. Generally, however, the technique should provide better-than-average candidate selections.

  7. Exergy analysis in the assessment of the sustainability of waste gas treatment systems.

    PubMed

    Dewulf, J; Van Langenhove, H; Dirckx, J

    2001-06-12

    This study focuses on the sustainability of different technological options for the treatment of waste gases from a waste water treatment plant loaded with volatile organic compounds. The options considered are biofiltration, active carbon adsorption and catalytic and thermal oxidation. The amount of resources and utilities to construct and operate each system have been investigated from the point of view of the Second Law of thermodynamics. The unit in which all resources are treated is Joules of exergy. It was concluded that biofiltration was the most exergetically efficient system. The cumulative exergy consumption of the resources and utilities for construction and operation have been quantified in exergy terms. Further on, the requirements for the abatement of emissions generated by operating the waste gas treatment systems and the amount of renewables have been taken into account in the assessment of the sustainability of the waste gas treatment technologies. Finally, a comparison between exergy analysis and life cycle analysis in assessing the sustainability of the waste gas treatment options, is presented.

  8. Numerical simulation and field test study of desulfurization wastewater evaporation treatment through flue gas.

    PubMed

    Deng, Jia-Jia; Pan, Liang-Ming; Chen, De-Qi; Dong, Yu-Quan; Wang, Cheng-Mu; Liu, Hang; Kang, Mei-Qiang

    2014-01-01

    Aimed at cost saving and pollution reduction, a novel desulfurization wastewater evaporation treatment system (DWETS) for handling wet flue gas desulfurization (WFGD) wastewater of a coal-fired power plant was studied. The system's advantages include simple process, and less investment and space. The feasibility of this system has been proven and the appropriate position and number of nozzles, the spray droplet size and flue gas temperature limitation have been obtained by computational fluid dynamics (CFD) simulation. The simulation results show that a longer duct, smaller diameter and higher flue gas temperature could help to increase the evaporation rate. The optimal DWETS design of Shangdu plant is 100 μm droplet sprayed by two nozzles located at the long duct when the flue gas temperature is 130 °C. Field tests were carried out based on the simulation results. The effects of running DWETS on the downstream devices have been studied. The results show that DWETS has a positive impact on ash removal efficiency and does not have any negative impact on the electrostatic precipitator (ESP), flue gas heat exchanger and WFGD. The pH values of the slurry of WFGD slightly increase when the DWETS is running. The simulation and field test of the DWETS show that it is a feasible future technology for desulfurization wastewater treatment.

  9. Multi-objective optimisation of wastewater treatment plant control to reduce greenhouse gas emissions.

    PubMed

    Sweetapple, Christine; Fu, Guangtao; Butler, David

    2014-05-15

    This study investigates the potential of control strategy optimisation for the reduction of operational greenhouse gas emissions from wastewater treatment in a cost-effective manner, and demonstrates that significant improvements can be realised. A multi-objective evolutionary algorithm, NSGA-II, is used to derive sets of Pareto optimal operational and control parameter values for an activated sludge wastewater treatment plant, with objectives including minimisation of greenhouse gas emissions, operational costs and effluent pollutant concentrations, subject to legislative compliance. Different problem formulations are explored, to identify the most effective approach to emissions reduction, and the sets of optimal solutions enable identification of trade-offs between conflicting objectives. It is found that multi-objective optimisation can facilitate a significant reduction in greenhouse gas emissions without the need for plant redesign or modification of the control strategy layout, but there are trade-offs to consider: most importantly, if operational costs are not to be increased, reduction of greenhouse gas emissions is likely to incur an increase in effluent ammonia and total nitrogen concentrations. Design of control strategies for a high effluent quality and low costs alone is likely to result in an inadvertent increase in greenhouse gas emissions, so it is of key importance that effects on emissions are considered in control strategy development and optimisation.

  10. Numerical simulation and field test study of desulfurization wastewater evaporation treatment through flue gas.

    PubMed

    Deng, Jia-Jia; Pan, Liang-Ming; Chen, De-Qi; Dong, Yu-Quan; Wang, Cheng-Mu; Liu, Hang; Kang, Mei-Qiang

    2014-01-01

    Aimed at cost saving and pollution reduction, a novel desulfurization wastewater evaporation treatment system (DWETS) for handling wet flue gas desulfurization (WFGD) wastewater of a coal-fired power plant was studied. The system's advantages include simple process, and less investment and space. The feasibility of this system has been proven and the appropriate position and number of nozzles, the spray droplet size and flue gas temperature limitation have been obtained by computational fluid dynamics (CFD) simulation. The simulation results show that a longer duct, smaller diameter and higher flue gas temperature could help to increase the evaporation rate. The optimal DWETS design of Shangdu plant is 100 μm droplet sprayed by two nozzles located at the long duct when the flue gas temperature is 130 °C. Field tests were carried out based on the simulation results. The effects of running DWETS on the downstream devices have been studied. The results show that DWETS has a positive impact on ash removal efficiency and does not have any negative impact on the electrostatic precipitator (ESP), flue gas heat exchanger and WFGD. The pH values of the slurry of WFGD slightly increase when the DWETS is running. The simulation and field test of the DWETS show that it is a feasible future technology for desulfurization wastewater treatment. PMID:25325555

  11. The best MSW treatment option by considering greenhouse gas emissions reduction: a case study in Georgia.

    PubMed

    Tayyeba, Omid; Olsson, Monika; Brandt, Nils

    2011-08-01

    The grave concern over climate change and new economic incentives such as the clean development mechanism (CDM) have given more weight to the potential of projects for reducing greenhouse gas (GHG) emissions. In the Adjara solid waste management project, even though the need for reductions in GHG emissions is acknowledged, it is not one of the key factors for selecting the most appropriate treatment method. This study addresses the benefit of various solid waste treatment methods that could be used in the Adjara project in terms of reducing GHG emissions. Seven different options for solid waste treatment are examined: open dumping as the baseline case, four options for landfill technology (no provision of landfill gas capture, landfill gas capture with open flare system, with enclosed flare system and with electricity generation), composting and anaerobic digestion with electricity production. CDM methodologies were used to quantify the amount of reductions for the scenarios. The study concludes sanitary landfill with capture and burning of landfill gas by an enclosed flare system could satisfy the requirements, including GHG reduction potential. The findings were tested for uncertainty and sensitivity by varying the data on composition and amount of waste and were found to be robust.

  12. Feasibility study for alternate fuels production: unconventional natural gas from wastewater treatment plants. Volume II, Appendix D. Final report

    SciTech Connect

    Overly, P.; Tawiah, K.

    1981-12-01

    Data are presented from a study performed to determined the feasibility of recovering methane from sewage at a typical biological secondary wastewater treatment plant. Three tasks are involved: optimization of digester gas; digester gas scrubbing; and application to the East Bay Municipal Utility District water pollution control plant. Results indicate that excess digester gas can be used economically at the wastewater treatment plant and that distribution and scrubbing can be complex and costly. (DMC) 193 references, 93 figures, 26 tables.

  13. Coke oven gas treatment and by-product plant of Magnitogorsk Integrated Iron and Steel Works

    SciTech Connect

    Egorov, V.N.; Anikin, G.J.; Gross, M.

    1995-12-01

    Magnitogorsk Integrated Iron and Steel Works, Russia, decided to erect a new coke oven gas treatment and by-product plant to replace the existing obsolete units and to improve the environmental conditions of the area. The paper deals with the technological concept and the design requirements. Commissioning is scheduled at the beginning of 1996. The paper describes H{sub 2}S and NH{sub 3} removal, sulfur recovery and ammonia destruction, primary gas cooling and electrostatic tar precipitation, and the distributed control system that will be installed.

  14. Wastewater treatment in the pulp-and-paper industry: A review of treatment processes and the associated greenhouse gas emission.

    PubMed

    Ashrafi, Omid; Yerushalmi, Laleh; Haghighat, Fariborz

    2015-08-01

    Pulp-and-paper mills produce various types of contaminants and a significant amount of wastewater depending on the type of processes used in the plant. Since the generated wastewaters can be potentially polluting and very dangerous, they should be treated in wastewater treatment plants before being released to the environment. This paper reviews different wastewater treatment processes used in the pulp-and-paper industry and compares them with respect to their contaminant removal efficiencies and the extent of greenhouse gas (GHG) emission. It also evaluates the impact of operating parameters on the performance of different treatment processes. Two mathematical models were used to estimate GHG emission in common biological treatment processes used in the pulp-and-paper industry. Nutrient removal processes and sludge treatment are discussed and their associated GHG emissions are calculated. Although both aerobic and anaerobic biological processes are appropriate for wastewater treatment, their combination known as hybrid processes showed a better contaminant removal capacity at higher efficiencies under optimized operating conditions with reduced GHG emission and energy costs. PMID:25982876

  15. Wastewater treatment in the pulp-and-paper industry: A review of treatment processes and the associated greenhouse gas emission.

    PubMed

    Ashrafi, Omid; Yerushalmi, Laleh; Haghighat, Fariborz

    2015-08-01

    Pulp-and-paper mills produce various types of contaminants and a significant amount of wastewater depending on the type of processes used in the plant. Since the generated wastewaters can be potentially polluting and very dangerous, they should be treated in wastewater treatment plants before being released to the environment. This paper reviews different wastewater treatment processes used in the pulp-and-paper industry and compares them with respect to their contaminant removal efficiencies and the extent of greenhouse gas (GHG) emission. It also evaluates the impact of operating parameters on the performance of different treatment processes. Two mathematical models were used to estimate GHG emission in common biological treatment processes used in the pulp-and-paper industry. Nutrient removal processes and sludge treatment are discussed and their associated GHG emissions are calculated. Although both aerobic and anaerobic biological processes are appropriate for wastewater treatment, their combination known as hybrid processes showed a better contaminant removal capacity at higher efficiencies under optimized operating conditions with reduced GHG emission and energy costs.

  16. Effect of plasma treatment on the gas sensor with single-walled carbon nanotube paste.

    PubMed

    Dong, Ki-Young; Ham, Dae-Jin; Kang, Byung Hyun; Lee, Keunsoo; Choi, Jinnil; Lee, Jin-Woo; Choi, Hyang Hee; Ju, Byeong-Kwon

    2012-01-30

    The effect of plasma treatment on the gas sensing properties of screen-printed single-walled carbon nanotube (SWCNT) pastes is reported. The gas sensors, using SWCNT pastes as a sensing material, were fabricated by photolithography and screen printing. The SWCNT pastes were deposited between interdigitated electrodes on heater membrane by screen printing. In order to functionalize the pastes, they were plasma treated using several gases which produce defects caused by reactive ion etching. The Ar and O(2) plasma-treated SWCNT pastes exhibited a large response to NO(2) exposure and the fluorinated gas, such as CF(4) and SF(6), plasma-treated SWCNT pastes exhibited a large response to NH(3) exposure. PMID:22284456

  17. Treatment of waste gas containing diethyldisulphide (DEDS) in a bench scale biofilter.

    PubMed

    Pandey, R A; Mudliar, S N; Borgaokar, S

    2009-01-01

    Waste gas containing diethyldisulphide (DEDS) is generated from various industries including pulp and paper, refinery, rayon and molasses based distilleries, etc. DEDS has odour threshold detection with an average concentration of 10(-9)mg/m(3) at 25 degrees C. DEDS is toxic to bacteria, fungus and also to mammals when exposed for a long period. Waste gas containing DEDS require proper treatment prior to discharge into the environment. DEDS containing waste gas was treated in a biofilter, packed with compost along with wooden chips and enriched with DEDS degrading microorganisms. The biofilter could remove DEDS to the extent of 94+/-5% at a loading of 1.60 g/m(3)/h with an empty bed retention time of 150s. At optimal operating conditions, the average moisture content required by the biofilter was in the range of 60-65%. The biodegradative products of DEDS were thiosulphate and sulphate.

  18. Treatment of waste gas containing diethyldisulphide (DEDS) in a bench scale biofilter.

    PubMed

    Pandey, R A; Mudliar, S N; Borgaokar, S

    2009-01-01

    Waste gas containing diethyldisulphide (DEDS) is generated from various industries including pulp and paper, refinery, rayon and molasses based distilleries, etc. DEDS has odour threshold detection with an average concentration of 10(-9)mg/m(3) at 25 degrees C. DEDS is toxic to bacteria, fungus and also to mammals when exposed for a long period. Waste gas containing DEDS require proper treatment prior to discharge into the environment. DEDS containing waste gas was treated in a biofilter, packed with compost along with wooden chips and enriched with DEDS degrading microorganisms. The biofilter could remove DEDS to the extent of 94+/-5% at a loading of 1.60 g/m(3)/h with an empty bed retention time of 150s. At optimal operating conditions, the average moisture content required by the biofilter was in the range of 60-65%. The biodegradative products of DEDS were thiosulphate and sulphate. PMID:18603425

  19. A biofilter integrated with gas membrane separation unit for the treatment of fluctuating styrene loads.

    PubMed

    Li, Lin; Lian, Jing; Han, Yunping; Liu, Junxin

    2012-05-01

    Biofiltration for volatile organic compound control in waste gas streams is best operated at steady contaminant loadings. To provide long-term stable operation of a biofilter under adverse contaminant feeding conditions, an integrated bioreactor system with a gas separation membrane module installed after a biofilter was proposed for styrene treatment. Styrene was treated effectively, with average styrene effluent concentrations maintained at less than 50 mg m(-3) and a total removal efficiency of over 96% achieved when the biofiltration column faced fluctuating loads. The maximum elimination capacity of the integrated bioreactor system was 93.8 g m(-3)h(-1), which was higher than that obtained with the biofiltration column alone. The combination of these two processes (microbial and chemical) led to more efficient elimination of styrene and buffering of the fluctuating loads. The factors on gas membrane separation, microbial characteristics in the integrated bioreactor and membrane fouling were also investigated in this study.

  20. Evaluation of chlorine dioxide gas treatment to inactivate Salmonella enterica on mungbean sprouts.

    PubMed

    Prodduk, Vara; Annous, Bassam A; Liu, Linshu; Yam, Kit L

    2014-11-01

    Although freshly sprouted beans and grains are considered to be a source of nutrients, they have been associated with foodborne outbreaks. Sprouts provide good matrices for microbial localization and growth due to optimal conditions of temperature and humidity while sprouting. Also, the lack of a kill step postsprouting is a major safety concern. The objective of this work was to evaluate the effectiveness of chlorine dioxide gas treatment to reduce Salmonella on artificially inoculated mungbean sprouts. The effectiveness of gaseous chlorine dioxide (0.5 mg/liter of air) with or without tumbling (mechanical mixing) was compared with an aqueous chlorine (200 ppm) wash treatment. Tumbling the inoculated sprouts during the chlorine dioxide gas application for 15, 30, and 60 min reduced Salmonella populations by 3.0, 4.0, and 5.5 log CFU/g, respectively, as compared with 3.0, 3.0, and 4.0 log CFU/g reductions obtained without tumbling, respectively. A 2.0 log CFU/g reduction in Salmonella was achieved with an aqueous chlorine wash. The difference in microbial reduction between chlorine dioxide gas versus aqueous chlorine wash points to the important role of surface topography, pore structure, bacterial attachment, and/or biofilm formation on sprouts. These data suggested that chlorine dioxide gas was capable of penetrating and inactivating cells that are attached to inaccessible sites and/or are within biofilms on the sprout surface as compared with an aqueous chlorine wash. Consequently, scanning electron microscopy imaging indicated that chlorine dioxide gas treatment was capable of penetrating and inactivating cells attached to inaccessible sites and within biofilms on the sprout surfaces.

  1. Effects of forming gas plasma treatment on low-temperature Cu–Cu direct bonding

    NASA Astrophysics Data System (ADS)

    Kim, Sungdong; Nam, Youngju; Eunkyung Kim, Sarah

    2016-06-01

    Low-temperature Cu–Cu direct bonding becomes of great importance as Cu is widely used as an interconnection material in the packaging industry. Preparing a clean surface is a key to successful Cu–Cu direct bonding. We investigated the effects of forming gas plasma treatment on the reduction of Cu oxide and Cu–Cu bonding temperature. As plasma input power and treatment time increased, Cu oxide could be effectively reduced, and this could be attributed to the enhanced chemical reaction between forming gas plasma and Cu oxide. When the bonding temperature was reduced from 415 to 300 °C, the bonding strength of the plasma-treated interface was increased from 1.8 to 5.55 J/m2 while that of the wet-treated interface was decreased.

  2. The integrated melter off-gas treatment systems at the West Valley Demonstration Project

    SciTech Connect

    Vance, R.F.

    1991-12-01

    The West Valley Demonstration project was established by an act of Congress in 1980 to solidify the high level radioactive liquid wastes produced from operation of the Western New York Nuclear Services Center from 1966 to 1972. The waste will be solidified as borosilicate glass. This report describes the functions, the controlling design criteria, and the resulting design of the melter off-gas treatment systems.

  3. Identifying key sources of uncertainty in the modelling of greenhouse gas emissions from wastewater treatment.

    PubMed

    Sweetapple, Christine; Fu, Guangtao; Butler, David

    2013-09-01

    This study investigates sources of uncertainty in the modelling of greenhouse gas emissions from wastewater treatment, through the use of local and global sensitivity analysis tools, and contributes to an in-depth understanding of wastewater treatment modelling by revealing critical parameters and parameter interactions. One-factor-at-a-time sensitivity analysis is used to screen model parameters and identify those with significant individual effects on three performance indicators: total greenhouse gas emissions, effluent quality and operational cost. Sobol's method enables identification of parameters with significant higher order effects and of particular parameter pairs to which model outputs are sensitive. Use of a variance-based global sensitivity analysis tool to investigate parameter interactions enables identification of important parameters not revealed in one-factor-at-a-time sensitivity analysis. These interaction effects have not been considered in previous studies and thus provide a better understanding wastewater treatment plant model characterisation. It was found that uncertainty in modelled nitrous oxide emissions is the primary contributor to uncertainty in total greenhouse gas emissions, due largely to the interaction effects of three nitrogen conversion modelling parameters. The higher order effects of these parameters are also shown to be a key source of uncertainty in effluent quality. PMID:23770480

  4. Identifying key sources of uncertainty in the modelling of greenhouse gas emissions from wastewater treatment.

    PubMed

    Sweetapple, Christine; Fu, Guangtao; Butler, David

    2013-09-01

    This study investigates sources of uncertainty in the modelling of greenhouse gas emissions from wastewater treatment, through the use of local and global sensitivity analysis tools, and contributes to an in-depth understanding of wastewater treatment modelling by revealing critical parameters and parameter interactions. One-factor-at-a-time sensitivity analysis is used to screen model parameters and identify those with significant individual effects on three performance indicators: total greenhouse gas emissions, effluent quality and operational cost. Sobol's method enables identification of parameters with significant higher order effects and of particular parameter pairs to which model outputs are sensitive. Use of a variance-based global sensitivity analysis tool to investigate parameter interactions enables identification of important parameters not revealed in one-factor-at-a-time sensitivity analysis. These interaction effects have not been considered in previous studies and thus provide a better understanding wastewater treatment plant model characterisation. It was found that uncertainty in modelled nitrous oxide emissions is the primary contributor to uncertainty in total greenhouse gas emissions, due largely to the interaction effects of three nitrogen conversion modelling parameters. The higher order effects of these parameters are also shown to be a key source of uncertainty in effluent quality.

  5. Selective Trapping of Volatile Fission Products with an Off-Gas Treatment System

    SciTech Connect

    B.R. Westphal; J.J. Park; J.M. Shin; G.I. Park; K.J. Bateman; D.L. Wahlquist

    2008-07-01

    A head-end processing step, termed DEOX for its emphasis on decladding via oxidation, is being developed for the treatment of spent oxide fuel by pyroprocessing techniques. The head-end step employs high temperatures to oxidize UO2 to U3O8 resulting in the separation of fuel from cladding and the removal of volatile fission products. Development of the head-end step is being performed in collaboration with the Korean Atomic Energy Research Institute (KAERI) through an International Nuclear Energy Research Initiative. Following the initial experimentation for the removal of volatile fission products, an off-gas treatment system was designed in conjunction with KAERI to collect specific fission gases. The primary volatile species targeted for trapping were iodine, technetium, and cesium. Each species is intended to be collected in distinct zones of the off-gas system and within those zones, on individual filters. Separation of the volatile off-gases is achieved thermally as well as chemically given the composition of the filter media. A description of the filter media and a basis for its selection will be given along with the collection mechanisms and design considerations. In addition, results from testing with the off-gas treatment system will be presented.

  6. Study of Plasma Treatment of Produced Water from Oil and Gas Exploration

    NASA Astrophysics Data System (ADS)

    Wright, Kamau

    Unconventional gas and hydraulic fracturing is helping to increase natural gas production, which is widely viewed in the U.S. as a key asset to bolstering a clean and energy-independent future. Safe and economical management and treatment of water produced during such processes remain of key importance. With the increase of hydrocarbon production and national shale gas production expected to increase threefold and account for nearly half of all natural gas produced by 2035, advanced water treatment and management processes must be investigated, to ensure water conservation and associated economic prudence. The state of the art of produced water treatment technologies is described including the efficacy of plasma to modulate the contents of such aqueous solutions, meeting target parameters and potentially enabling the operation of other treatment technologies. Among other effects, progress is presented on the enhancement of an arc-in-water system to remove bicarbonate ions and prevent the mineral fouling ability of water which causes formation of CaCO3 in heat exchangers and distillation units. Qualitative and quantitative treatment targets of produced water treatment are discussed. Experimental work is conducted to test theories and identify and reproduce favorable effects useful to treating wastewaters. Plasma arc-in-water systems demonstrated capability of producing bicarbonate-depleted wastewaters, with experiments with gas-field produced waters indicating that generation of H+ ions plays a greater role in bicarbonate ion removal than local heating. Tests showed abatement of bicarbonate ions from a range of 684--778 mg/L down to zero. Subsequent scaling/fouling tests with waters ranging from 0 to 500 mg/L bicarbonate ions, in the presence of high calcium ion concentrations, showed that scale thickness, as well as mass on a 1-kW heating element was an order of magnitude less for process water containing 100 mg/L bicarbonate ions compared to process water with 500

  7. Analytical determination of the suitability of different processes for the treatment of odorous waste gas.

    PubMed

    Ranau, R; Kleeberg, K K; Schlegelmilch, M; Streese, J; Stegmann, R; Steinhart, H

    2005-01-01

    In order to determine the efficiency of different treatment systems for the reduction of odorous emissions, a gas chromatographic method followed by simultaneous mass spectrometry and olfactometry (GC-MS/O) was developed. Samples from a coffee bean roasting and a fat and oil processing plant were analyzed, respectively. The results were compared with the data obtained by olfactometric measurements. At a coffee bean roasting plant, cooling gases were analyzed prior to and after treatment in a full scale bioscrubber. The GC-MS/O analysis showed that the amounts of aldehydes and ketones decreased after treatment of cooling gases of coffee bean roasting in the bioscrubber, whereas the contents of the heterocyclic compounds, like pyridine and the pyrazines, and acetophenone and guaiacol remained almost unchanged. The amounts of dimethyl disulfide, 3-hydroxy-2-butanone, and the carboxylic acids increased after bioscrubber treatment. Furthermore, the performance of each stage of a combined experimental plant for the treatment of exhaust air of fat and oil processing was investigated. This treatment plant consisted of a bioscrubber, a biofilter, and an activated carbon adsorber. The important odor-active compounds of the exhaust air of fat and oil processing were the typical fat oxidation products (aldehydes, ketones) and with lower importance 2-pentylfuran, a few terpenes and aromates. Again, the key odor-active compounds, aldehydes and ketones, were degraded in the bioscrubber. Further degradation of aliphatic, unsaturated, methylated, and cyclic alkanes, as well as aromates, terpenes, and furans by the biofilter was observed. After the last treatment stage, the activated carbon filter, only small amounts of aliphatic, unsaturated, methylated, and cyclic alkanes and aromates remained in the waste gas. For both applications, the results of the developed GC-MS/O method correlated very well with olfactometric measurements.

  8. Reductions in greenhouse gas (GHG) generation and energy consumption in wastewater treatment plants.

    PubMed

    Yerushalmi, L; Ashrafi, O; Haghighat, F

    2013-01-01

    Greenhouse gas (GHG) emission and energy consumption by on-site and off-site sources were estimated in two different wastewater treatment plants that used physical-chemical or biological processes for the removal of contaminants, and an anaerobic digester for sludge treatment. Physical-chemical treatment processes were used in the treatment plant of a locomotive repair factory that processed wastewater at 842 kg chemical oxygen demand per day. Approximately 80% of the total GHG emission was related to fossil fuel consumption for energy production. The emission of GHG was reduced by 14.5% with the recovery of biogas that was generated in the anaerobic digester and its further use as an energy source, replacing fossil fuels. The examined biological treatment system used three alternative process designs for the treatment of effluents from pulp and paper mills that processed wastewater at 2,000 kg biochemical oxygen demand per day. The three designs used aerobic, anaerobic, or hybrid aerobic/anaerobic biological processes for the removal of carbonaceous contaminants, and nitrification/denitrification processes for nitrogen removal. Without the recovery and use of biogas, the aerobic, anaerobic, and hybrid treatment systems generated 3,346, 6,554 and 7,056 kg CO(2)-equivalent/day, respectively, while the generated GHG was reduced to 3,152, 6,051, and 6,541 kg CO(2)-equivalent/day with biogas recovery. The recovery and use of biogas was shown to satisfy and exceed the energy needs of the three examined treatment plants. The reduction of operating temperature of the anaerobic digester and anaerobic reactor by 10°C reduced energy demands of the treatment plants by 35.1, 70.6 and 62.9% in the three examined treatment systems, respectively.

  9. Low-Carbon Watershed Management: Potential of Greenhouse Gas Reductions from Wastewater Treatment in Rural Vietnam

    PubMed Central

    Mohan, Geetha; Jian, Pu; Takemoto, Kazuhiko; Fukushi, Kensuke

    2016-01-01

    Currently in many cities and rural areas of Vietnam, wastewater is discharged to the environment without any treatment, which emits considerable amount of greenhouse gas (GHG), particularly methane. In this study, four GHG emission scenarios were examined, as well as the baseline scenario, in order to verify the potential of GHG reduction from domestic wastewater with adequate treatment facilities. The ArcGIS and ArcHydro tools were employed to visualize and analyze GHG emissions resulting from discharge of untreated wastewater, in rural areas of Vu Gia Thu Bon river basin, Vietnam. By applying the current IPCC guidelines for GHG emissions, we found that a reduction of GHG emissions can be achieved through treatment of domestic wastewater in the studied area. Compared with baseline scenario, a maximum 16% of total GHG emissions can be reduced, in which 30% of households existing latrines are substituted by Japanese Johkasou technology and other 20% of domestic wastewater is treated by conventional activated sludge.

  10. Low-Carbon Watershed Management: Potential of Greenhouse Gas Reductions from Wastewater Treatment in Rural Vietnam

    PubMed Central

    Mohan, Geetha; Jian, Pu; Takemoto, Kazuhiko; Fukushi, Kensuke

    2016-01-01

    Currently in many cities and rural areas of Vietnam, wastewater is discharged to the environment without any treatment, which emits considerable amount of greenhouse gas (GHG), particularly methane. In this study, four GHG emission scenarios were examined, as well as the baseline scenario, in order to verify the potential of GHG reduction from domestic wastewater with adequate treatment facilities. The ArcGIS and ArcHydro tools were employed to visualize and analyze GHG emissions resulting from discharge of untreated wastewater, in rural areas of Vu Gia Thu Bon river basin, Vietnam. By applying the current IPCC guidelines for GHG emissions, we found that a reduction of GHG emissions can be achieved through treatment of domestic wastewater in the studied area. Compared with baseline scenario, a maximum 16% of total GHG emissions can be reduced, in which 30% of households existing latrines are substituted by Japanese Johkasou technology and other 20% of domestic wastewater is treated by conventional activated sludge. PMID:27699202

  11. Natural Gas Residual Fluids: Sources, Endpoints, and Organic Chemical Composition after Centralized Waste Treatment in Pennsylvania.

    PubMed

    Getzinger, Gordon J; O'Connor, Megan P; Hoelzer, Kathrin; Drollette, Brian D; Karatum, Osman; Deshusses, Marc A; Ferguson, P Lee; Elsner, Martin; Plata, Desiree L

    2015-07-21

    Volumes of natural gas extraction-derived wastewaters have increased sharply over the past decade, but the ultimate fate of those waste streams is poorly characterized. Here, we sought to (a) quantify natural gas residual fluid sources and endpoints to bound the scope of potential waste stream impacts and (b) describe the organic pollutants discharged to surface waters following treatment, a route of likely ecological exposure. Our findings indicate that centralized waste treatment facilities (CWTF) received 9.5% (8.5 × 10(8) L) of natural gas residual fluids in 2013, with some facilities discharging all effluent to surface waters. In dry months, discharged water volumes were on the order of the receiving body flows for some plants, indicating that surface waters can become waste-dominated in summer. As disclosed organic compounds used in high volume hydraulic fracturing (HVHF) vary greatly in physicochemical properties, we deployed a suite of analytical techniques to characterize CWTF effluents, covering 90.5% of disclosed compounds. Results revealed that, of nearly 1000 disclosed organic compounds used in HVHF, only petroleum distillates and alcohol polyethoxylates were present. Few analytes targeted by regulatory agencies (e.g., benzene or toluene) were observed, highlighting the need for expanded and improved monitoring efforts at CWTFs.

  12. Method of measurement of VOCs in the off-gas and wastewater of wastewater treatment plants

    SciTech Connect

    Min Wang; Keener, T.C.; Orton, T.L.; Zhu, H.; Bishop, P.; Pekonen, S.; Siddiqui, K.

    1997-12-31

    VOCs need to be controlled according to Title 3 of the 1990 Clean Air Act Amendments (CAAA), so an accurate estimation of the total VOC emissions must be attained. This paper reports on a study where EPA method 624 was revised so that this method could be used for VOC analysis both in the water and off-gas of wastewater treatment plants. The revised method uses the same approach and equipment as water and soil analyses, thereby providing a great time and cost advantage for anyone needing to perform this type of analysis. Without using a cryogenic preconcentration step, gas samples from Tedlar bags are easily analyzed to concentrations of approximately 20 ppb using scan mode in a GC-MS unit. For the wastewater, scan mode was still used for the identification, but Selected Ion Monitoring (SIM) mode was used for quantitative analysis because of lower VOC concentration in the water. The results show that this method`s detection limit (MDL) was lowered 2--3 orders of magnitude when compared with scan mode. The modified method has been successfully applied to the identification and quantitative analysis of wastewater and off-gas VOCs from a publicly owned treatment works (POTW) aeration basin (120 MGD).

  13. Natural Gas Residual Fluids: Sources, Endpoints, and Organic Chemical Composition after Centralized Waste Treatment in Pennsylvania.

    PubMed

    Getzinger, Gordon J; O'Connor, Megan P; Hoelzer, Kathrin; Drollette, Brian D; Karatum, Osman; Deshusses, Marc A; Ferguson, P Lee; Elsner, Martin; Plata, Desiree L

    2015-07-21

    Volumes of natural gas extraction-derived wastewaters have increased sharply over the past decade, but the ultimate fate of those waste streams is poorly characterized. Here, we sought to (a) quantify natural gas residual fluid sources and endpoints to bound the scope of potential waste stream impacts and (b) describe the organic pollutants discharged to surface waters following treatment, a route of likely ecological exposure. Our findings indicate that centralized waste treatment facilities (CWTF) received 9.5% (8.5 × 10(8) L) of natural gas residual fluids in 2013, with some facilities discharging all effluent to surface waters. In dry months, discharged water volumes were on the order of the receiving body flows for some plants, indicating that surface waters can become waste-dominated in summer. As disclosed organic compounds used in high volume hydraulic fracturing (HVHF) vary greatly in physicochemical properties, we deployed a suite of analytical techniques to characterize CWTF effluents, covering 90.5% of disclosed compounds. Results revealed that, of nearly 1000 disclosed organic compounds used in HVHF, only petroleum distillates and alcohol polyethoxylates were present. Few analytes targeted by regulatory agencies (e.g., benzene or toluene) were observed, highlighting the need for expanded and improved monitoring efforts at CWTFs. PMID:26147419

  14. The role of bioremediation in the treatment of gas industry wastes

    SciTech Connect

    Paterek, J.R.

    1993-12-31

    Bioremediation is a technology that integrates microbiology, ecology, chemistry, geology, and engineering in order to solve a major problem in today`s society, restoration of our environment This is not a collection of abstract disciplines, but a new and functional technology based on processes with a long, successful history, that is, biological waste treatment. Sewage and wastewater treatment, composting, and landfills are mature sources and starting points of this technology, but the complexity of manmade or man-released hazardous wastes in the heterogeneous matrices of contaminated water, soil, and sediment requires diligent research and development for successful application of bioremediation. The technology is being applied to various sites contaminated by organic and inorganic toxic compounds or elements, and these processes, techniques, and data can be tested and applied to the gas industry`s contaminated environments. An immediate opportunity for the application of this technology is manufactured town gas sites. Ongoing research into the remediation of polynuclear aromatic hydrocarbons, polychlorinated biphenyls, and cyanides - which are common gas industry associated wastes - is leading to an awareness of limitations of biodegradation of these compounds and to possible technical and engineering paradigms required to overcome or minimize them. Future research in microbiology, ecology, and engineering of bioremediation should lead to effective remediation technologies for present and future challenges facing this industry.

  15. The effect of heat treatment on the magnitude and composition of residual gas in sealed silica glass ampoules

    NASA Technical Reports Server (NTRS)

    Palosz, W.; Szofran, F. R.; Lehoczky, S. L.

    1994-01-01

    The residual gas pressure and composition in sealed silica glass ampoules as a function of different treatment procedures has been investigated. The dependence of the residual gas on the outgassing and annealing parameters has been determined. The effects of the fused silica brand, of the ampoule fabrication, and of post-outgassing procedures have been evaluated.

  16. Developments in odour control and waste gas treatment biotechnology: a review.

    PubMed

    Burgess, J E; Parsons, S A; Stuetz, R M

    2001-02-01

    Waste and wastewater treatment processes produce odours, which can cause a nuisance to adjacent populations and contribute significantly to atmospheric pollution. Sulphurous compounds are responsible for acid rain and mist; many organic compounds of industrial origin contribute to airborne public health concerns, as well as environmental problems. Waste gases from industry have traditionally been treated using physicochemical processes, such as scrubbing, adsorption, condensation, and oxidation, however, biological treatment of waste gases has gained support as an effective and economical option in the past few decades. One emergent technique for biological waste gas treatment is the use of existing activated sludge plants as bioscrubbers, thus treating the foul air generated by other process units of the wastewater treatment system on site, with no requirement for additional units or for interruption of wastewater treatment. Limited data are available regarding the performance of activated sludge diffusion of odorous air in spite of numerous positive reports from full-scale applications in North America. This review argues that the information available is insufficient for precise process design and optimization, and simultaneous activated sludge treatment of wastewater and airborne odours could be adopted worldwide.

  17. Shale gas produced water treatment using innovative microbial capacitive desalination cell.

    PubMed

    Stoll, Zachary A; Forrestal, Casey; Ren, Zhiyong Jason; Xu, Pei

    2015-01-01

    The rapid development of unconventional oil and gas production has generated large amounts of wastewater for disposal, raising significant environmental and public health concerns. Treatment and beneficial use of produced water presents many challenges due to its high concentrations of petroleum hydrocarbons and salinity. The objectives of this study were to investigate the feasibility of treating actual shale gas produced water using a bioelectrochemical system integrated with capacitive deionization-a microbial capacitive desalination cell (MCDC). Microbial degradation of organic compounds in the anode generated an electric potential that drove the desalination of produced water. Sorption and biodegradation resulted in a combined organic removal rate of 6.4 mg dissolved organic carbon per hour in the reactor, and the MCDC removed 36 mg salt per gram of carbon electrode per hour from produced water. This study is a proof-of-concept that the MCDC can be used to combine organic degradation with desalination of contaminated water without external energy input.

  18. [INVITED] Laser gas assisted treatment of Ti-alloy: Analysis of surface characteristics

    NASA Astrophysics Data System (ADS)

    Yilbas, B. S.; Ali, H.; Karatas, C.

    2016-04-01

    Laser gas assisted treatment of Ti6Al4V alloy surface is carried out and nitrogen/oxygen mixture with partial pressure of PO2/PN2=1/3 is introduced during the surface treatment process. Analytical tools are used to characterize the laser treated surfaces. The fracture toughness at the surface and the residual stress in the surface region of the laser treated layer are measured. Scratch tests are carried out to determine the friction coefficient of the treated surface. It is found that closely spaced regular laser scanning tracks generates a self-annealing effect in the laser treated layer while lowering the stress levels in the treated region. Introducing high pressure gas mixture impingement at the surface results in formation of oxide and nitride species including, TiO, TiO2, TiN and TiOxNy in the surface region. A dense layer consisting of fine size grains are formed in the surface region of the laser treated layer, which enhances the microhardness at the surface. The fracture toughness reduces after the laser treatment process because of the microhardness enhancement at the surface. The residual stress formed is comprehensive, which is in the order of -350 MPa.

  19. The Energy, Greenhouse Gas Emissions, and Cost Implications of Municipal Water Supply & Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Rodriguez-Winter, Thelma

    All man-made structures and materials have a design life. Across the United States there is a common theme for our water and wastewater treatment facilities and infrastructure. The design life of many of our mid 20 th century water and wastewater infrastructures in the United States have reached or are reaching life expectancy limits (ASCE, 2010). To compound the financial crisis of keeping up with the degradation, meeting and exceeding quality standards has never been more important in order to protect local fresh water supplies. This thesis analyzes the energy consumption of a municipal water and wastewater treatment system from a Lake Erie intake through potable treatment and back through wastewater treatment then discharge. The system boundary for this thesis includes onsite energy consumed by the treatment system and distribution/reclamation system as well as the energy consumed by the manufacturing of treatment chemicals applied during the study periods. By analyzing energy consumption, subsequent implications from greenhouse gas emissions and financial expenditures were quantified. Through the segregation of treatment and distribution processes from non-process energy consumption, such as heating, lighting, and air handling, this study identified that the potable water treatment system consumed an annual average of 2.42E+08 kBtu, spent 5,812,144 for treatment and distribution, and emitted 28,793 metric tons of CO2 equivalent emissions. Likewise, the wastewater treatment system consumed an annual average of 2.45E+08 kBtu, spent 3,331,961 for reclamation and treatment, and emitted 43,780 metric tons of CO2 equivalent emissions. The area with the highest energy usage, financial expenditure, and greenhouse gas emissions for the potable treatment facility and distribution system was from the manufacturing of the treatment chemicals, 1.10E+08 kBtu, 3.7 million, and 17,844 metric tons of CO2 equivalent, respectively. Of the onsite energy (1.4E-03 kWh per gallon

  20. Modelling the behaviour of mechanical biological treatment outputs in landfills using the GasSim model.

    PubMed

    Donovan, S M; Bateson, T; Gronow, J R; Voulvoulis, N

    2010-03-15

    The pretreatment of the biodegradable components of municipal solid waste (MSW) has been suggested as a method of reducing landfill gas emissions. Mechanical biological treatment (MBT) is the technology being developed to provide this reduction in biodegradability, either as an alternative to source segregated collection or for dealing with residual MSW which still contains high levels of biodegradable waste. The compost like outputs (CLOs) from MBT plants can be applied to land as a soil conditioner; treated to produce a solid recovered fuel (SRF) or landfilled. In this study the impact that landfilling of these CLOs will have on gaseous emissions is investigated. It is important that the gas production behaviour of landfilled waste is well understood, especially in European member states where the mitigation of gaseous emissions is a legal requirement. Results of an experiment carried out to characterise the biodegradable components of pretreated biowastes have been used with the GasSim model to predict the long term emissions behaviour of landfills accepting these wastes, in varying quantities. The landfill directive also enforces the mitigation of potential methane emissions from landfills, and the ability of landfill operators to capture gaseous emissions from low emitting landfills of the future is discussed, as well as new techniques that could be used for the mitigation of methane generation. PMID:20092874

  1. Ozone Gas as a Benign Sterilization Treatment for PLGA Nanofiber Scaffolds.

    PubMed

    Rediguieri, Carolina Fracalossi; Pinto, Terezinha de Jesus Andreoli; Bou-Chacra, Nadia Araci; Galante, Raquel; de Araújo, Gabriel Lima Barros; Pedrosa, Tatiana do Nascimento; Maria-Engler, Silvya Stuchi; De Bank, Paul A

    2016-04-01

    The use of electrospun nanofibers for tissue engineering and regenerative medicine applications is a growing trend as they provide improved support for cell proliferation and survival due, in part, to their morphology mimicking that of the extracellular matrix. Sterilization is a critical step in the fabrication process of implantable biomaterial scaffolds for clinical use, but many of the existing methods used to date can negatively affect scaffold properties and performance. Poly(lactic-co-glycolic acid) (PLGA) has been widely used as a biodegradable polymer for 3D scaffolds and can be significantly affected by current sterilization techniques. The aim of this study was to investigate pulsed ozone gas as an alternative method for sterilizing PLGA nanofibers. The morphology, mechanical properties, physicochemical properties, and response of cells to PLGA nanofiber scaffolds were assessed following different degrees of ozone gas sterilization. This treatment killed Geobacillus stearothermophilus spores, the most common biological indicator used for validation of sterilization processes. In addition, the method preserved all of the characteristics of nonsterilized PLGA nanofibers at all degrees of sterilization tested. These findings suggest that ozone gas can be applied as an alternative method for sterilizing electrospun PLGA nanofiber scaffolds without detrimental effects. PMID:26757850

  2. Design Of A Sorbent/desorbent Unit For Sample Pre-treatment Optimized For QMB Gas Sensors

    SciTech Connect

    Pennazza, G.; Cristina, S.; Santonico, M.; Martinelli, E.; Di Natale, C.; D'Amico, A.; Paolesse, R.

    2009-05-23

    Sample pre-treatment is a typical procedure in analytical chemistry aimed at improving the performance of analytical systems. In case of gas sensors sample pre-treatment systems are devised to overcome sensors limitations in terms of selectivity and sensitivity. For this purpose, systems based on adsorption and desorption processes driven by temperature conditioning have been illustrated. The involvement of large temperature ranges may pose problems when QMB gas sensors are used. In this work a study of such influences on the overall sensing properties of QMB sensors are illustrated. The results allowed the design of a pre-treatment unit coupled with a QMB gas sensors array optimized to operate in a suitable temperatures range. The performance of the system are illustrated by the partially separation of water vapor in a gas mixture, and by substantial improvement of the signal to noise ratio.

  3. Greenhouse gas emissions from mechanical and biological waste treatment of municipal waste.

    PubMed

    Clemens, J; Cuhls, C

    2003-06-01

    The mechanical and biological waste treatment (MBT) is an increasingly important technology for the treatment of municipal solid waste (MSW) before landfilling. This process includes composting of the material with intensive aeration in order to minimize the organic fraction that may induce methane and leachate emissions after landfilling. The exhaust air is treated by biofilters to remove odorous and volatile organic compounds. The emission of direct and indirect greenhouse gases, namely methane (CH4), carbon dioxide (CO2), ammonia (NH3), nitric (NO) and nitrous oxide (N2O) was studied in four existing treatment plants. All gases except NO were emitted from the composting material. The emission factors were 12 to 185 kg ton(-1) substrate for CO2, 6-12 x 10(3) g ton(-1) substrate for CH4, 1.44 to 378 g ton(-1) substrate for N2O and 18-1150 g ton(-1) for NH3. In general, emission factors increased with increasing treatment time. The biofilters had no net effect on CH4, but removed 13-89% of the NH3. For CO2 the biofilters were a small, for N2O a major and for NO the exclusive source. Approximately 26% of the NH3-N that was removed in the biofilter was transformed into N2O when NH3 was the exclusive nitrogen source. Assuming that all municipal waste was treated by MBT, the emissions would account for 0.3 to 5% of the N2O and for 0.1 to 3% of the CH4 emissions in Germany, respectively. Optimising aeration and removing NH3 before the exhaust gas enters the biofilter could lead to reduced greenhouse gas emissions.

  4. Comparison of alternative flue gas dry treatment technologies in waste-to-energy processes.

    PubMed

    Dal Pozzo, Alessandro; Antonioni, Giacomo; Guglielmi, Daniele; Stramigioli, Carlo; Cozzani, Valerio

    2016-05-01

    Acid gases such as HCl and SO2 are harmful both for human health and ecosystem integrity, hence their removal is a key step of the flue gas treatment of Waste-to-Energy (WtE) plants. Methods based on the injection of dry sorbents are among the Best Available Techniques for acid gas removal. In particular, systems based on double reaction and filtration stages represent nowadays an effective technology for emission control. The aim of the present study is the simulation of a reference two-stage (2S) dry treatment system performance and its comparison to three benchmarking alternatives based on single stage sodium bicarbonate injection. A modelling procedure was applied in order to identify the optimal operating configuration of the 2S system for different reference waste compositions, and to determine the total annual cost of operation. Taking into account both operating and capital costs, the 2S system appears the most cost-effective solution for medium to high chlorine content wastes. A Monte Carlo sensitivity analysis was carried out to assess the robustness of the results.

  5. Comparison of alternative flue gas dry treatment technologies in waste-to-energy processes.

    PubMed

    Dal Pozzo, Alessandro; Antonioni, Giacomo; Guglielmi, Daniele; Stramigioli, Carlo; Cozzani, Valerio

    2016-05-01

    Acid gases such as HCl and SO2 are harmful both for human health and ecosystem integrity, hence their removal is a key step of the flue gas treatment of Waste-to-Energy (WtE) plants. Methods based on the injection of dry sorbents are among the Best Available Techniques for acid gas removal. In particular, systems based on double reaction and filtration stages represent nowadays an effective technology for emission control. The aim of the present study is the simulation of a reference two-stage (2S) dry treatment system performance and its comparison to three benchmarking alternatives based on single stage sodium bicarbonate injection. A modelling procedure was applied in order to identify the optimal operating configuration of the 2S system for different reference waste compositions, and to determine the total annual cost of operation. Taking into account both operating and capital costs, the 2S system appears the most cost-effective solution for medium to high chlorine content wastes. A Monte Carlo sensitivity analysis was carried out to assess the robustness of the results. PMID:26951719

  6. Stability assessment of gas mixtures containing monoterpenes in varying cylinder materials and treatments.

    PubMed

    Rhoderick, George C; Lin, Janice

    2013-05-01

    Studies of climate change increasingly recognize the diverse influences exerted by monoterpenes in the atmosphere, including roles in particulates, ozone formation, and oxidizing potential. Measurements of key monoterpenes suggest atmospheric mole fractions ranging from low pmol/mol (parts-per-trillion; ppt) to nmol/mol (parts-per-billion; ppb), depending on location and compound. To accurately establish the mole fraction trends, assess the role of monoterpenes in atmospheric chemistry, and relate measurement records from many laboratories and researchers, it is essential to have good calibration standards. The feasibility of preparing well-characterized, stable gas cylinder standards for monoterpenes at the nmol/mol level was previously tested using treated (Aculife IV) aluminum gas cylinders at NIST. Results for 4 of the 11 monoterpenes, monitored versus an internal standard of benzene, indicated stability in these treated aluminum gas cylinders for over 6 months and projected long-term (years) stability. However, the mole fraction of the key monoterpene β-pinene decreased, while the mole fractions of α-pinene, d-limonene (R-(+)-limonene), p-cymene, and camphene (a terpene not present in the initial gas mixture) increased, indicating a chemical transformation of β-pinene to these species. A similar pattern of decreasing mole fraction was observed in α-pinene where growth of d-limonene, p-cymene, and camphene has been observed in treated gas cylinders prepared with a mixture of just α-pinene and benzene as the internal standard. The current research discusses the testing of other cylinders and treatments for the potential of long-term stability of monoterpenes in a gas mixture. In this current study, a similar pattern of decreasing mole fraction, although somewhat improved short-term stability, was observed for β-pinene and α-pinene, with growth of d-limonene, p-cymene, and camphene, in nickel-plated carbon steel cylinders. β-Pinene and α-pinene showed

  7. Influence of methanethiol on biological sulphide oxidation in gas treatment system.

    PubMed

    Roman, Pawel; Bijmans, Martijn F M; Janssen, Albert J H

    2016-01-01

    Inorganic and organic sulphur compounds such as hydrogen sulphide (H2S) and thiols (RSH) are unwanted components in sour gas streams (e.g. biogas and refinery gases) because of their toxicity, corrosivity and bad smell. Biological treatment processes are often used to remove H2S at small and medium scales (<50 tons per day of H2S). Preliminarily research by our group focused on achieving maximum sulphur production from biological H2S oxidation in the presence of methanethiol. In this paper the underlying principles have been further studied by assessing the effect of methanethiol on the biological conversion of H2S under a wide range of redox conditions covering not only sulphur but also sulphate-producing conditions. Furthermore, our experiments were performed in an integrated system consisting of a gas absorber and a bioreactor in order to assess the effect of methanethiol on the overall gas treatment efficiency. This study shows that methanethiol inhibits the biological oxidation of H2S to sulphate by way of direct suppression of the cytochrome c oxidase activity in biomass, whereas the oxidation of H2S to sulphur was hardly affected. We estimated the kinetic parameters of biological H2S oxidation that can be used to develop a mathematical model to quantitatively describe the biodesulphurization process. Finally, it was found that methanethiol acts as a competitive inhibitor; therefore, its negative effect can be minimized by increasing the enzyme (biomass) concentration and the substrate (sulphide) concentration, which in practice means operating the biodesulphurization systems under low redox conditions.

  8. The Energy, Greenhouse Gas Emissions, and Cost Implications of Municipal Water Supply & Wastewater Treatment

    NASA Astrophysics Data System (ADS)

    Rodriguez-Winter, Thelma

    All man-made structures and materials have a design life. Across the United States there is a common theme for our water and wastewater treatment facilities and infrastructure. The design life of many of our mid 20 th century water and wastewater infrastructures in the United States have reached or are reaching life expectancy limits (ASCE, 2010). To compound the financial crisis of keeping up with the degradation, meeting and exceeding quality standards has never been more important in order to protect local fresh water supplies. This thesis analyzes the energy consumption of a municipal water and wastewater treatment system from a Lake Erie intake through potable treatment and back through wastewater treatment then discharge. The system boundary for this thesis includes onsite energy consumed by the treatment system and distribution/reclamation system as well as the energy consumed by the manufacturing of treatment chemicals applied during the study periods. By analyzing energy consumption, subsequent implications from greenhouse gas emissions and financial expenditures were quantified. Through the segregation of treatment and distribution processes from non-process energy consumption, such as heating, lighting, and air handling, this study identified that the potable water treatment system consumed an annual average of 2.42E+08 kBtu, spent 5,812,144 for treatment and distribution, and emitted 28,793 metric tons of CO2 equivalent emissions. Likewise, the wastewater treatment system consumed an annual average of 2.45E+08 kBtu, spent 3,331,961 for reclamation and treatment, and emitted 43,780 metric tons of CO2 equivalent emissions. The area with the highest energy usage, financial expenditure, and greenhouse gas emissions for the potable treatment facility and distribution system was from the manufacturing of the treatment chemicals, 1.10E+08 kBtu, 3.7 million, and 17,844 metric tons of CO2 equivalent, respectively. Of the onsite energy (1.4E-03 kWh per gallon

  9. TREATMENT OF PRODUCED OIL AND GAS WATERS WITH SURFACTANT-MODIFIED ZEOLITE

    SciTech Connect

    Lynn E. Katz; R.S. Bowman; E.J. Sullivan

    2003-11-01

    Co-produced water from the oil and gas industry accounts for a significant waste stream in the United States. It is by some estimates the largest single waste stream in the country, aside from nonhazardous industrial wastes. Characteristics of produced water include high total dissolved solids content, dissolved organic constituents such as benzene and toluene, an oil and grease component, and chemicals added during the oil-production process. While most of the produced water is disposed via reinjection, some must be treated to remove organic constituents before the water is discharged. Current treatment options are successful in reducing the organic content; however, they cannot always meet the levels of current or proposed regulations for discharged water. Therefore, an efficient, cost-effective treatment technology is needed. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. In addition, the low cost of natural zeolites makes their use attractive in water-treatment applications. This report summarizes the work and results of this four-year project. We tested the effectiveness of surfactant-modified zeolite (SMZ) for removal of BTEX with batch and column experiments using waters with BTEX concentrations that are comparable to those of produced waters. The data from our experimental investigations showed that BTEX sorption to SMZ can be described by a linear isotherm model, and competitive effects between compounds were not significant. The SMZ can be readily regenerated using air stripping. We field-tested a prototype SMZ-based water treatment system at produced water treatment facilities and found that the SMZ successfully removes BTEX from produced waters as predicted by laboratory studies. When compared to other existing treatment technologies, the cost of the SMZ system is very competitive. Furthermore, the SMZ system is relatively compact, does not require the storage of

  10. Greenhouse gas emissions from landfill leachate treatment plants: a comparison of young and aged landfill.

    PubMed

    Wang, Xiaojun; Jia, Mingsheng; Chen, Xiaohai; Xu, Ying; Lin, Xiangyu; Kao, Chih Ming; Chen, Shaohua

    2014-07-01

    With limited assessment, leachate treatment of a specified landfill is considered to be a significant source of greenhouse gas (GHG) emissions. In our study, the cumulative GHG emitted from the storage ponds and process configurations that manage fresh or aged landfill leachate were investigated. Our results showed that strong CH4 emissions were observed from the fresh leachate storage pond, with the fluxes values (2219-26,489 mg Cm(-2)h(-1)) extremely higher than those of N2O (0.028-0.41 mg Nm(-2)h(-1)). In contrast, the emission values for both CH4 and N2O were low for the aged leachate tank. N2O emissions became dominant once the leachate entered the treatment plants of both systems, accounting for 8-12% of the removal of N-species gases. Per capita, the N2O emission based on both leachate treatment systems was estimated to be 7.99 g N2O-N capita(-1)yr(-1). An increase of 80% in N2O emissions was observed when the bioreactor pH decreased by approximately 1 pH unit. The vast majority of carbon was removed in the form of CO2, with a small portion as CH4 (<0.3%) during both treatment processes. The cumulative GHG emissions for fresh leachate storage ponds, fresh leachate treatment system and aged leachate treatment system were 19.10, 10.62 and 3.63 Gg CO(2) eq yr(-1), respectively, for a total that could be transformed to 9.09 kg CO(2) eq capita(-1)yr(-1).

  11. Coalbed Methane Procduced Water Treatment Using Gas Hydrate Formation at the Wellhead

    SciTech Connect

    BC Technologies

    2009-12-30

    Water associated with coalbed methane (CBM) production is a significant and costly process waste stream, and economic treatment and/or disposal of this water is often the key to successful and profitable CBM development. In the past decade, advances have been made in the treatment of CBM produced water. However, produced water generally must be transported in some fashion to a centralized treatment and/or disposal facility. The cost of transporting this water, whether through the development of a water distribution system or by truck, is often greater than the cost of treatment or disposal. To address this economic issue, BC Technologies (BCT), in collaboration with Oak Ridge National Laboratory (ORNL) and International Petroleum Environmental Consortium (IPEC), proposed developing a mechanical unit that could be used to treat CBM produced water by forming gas hydrates at the wellhead. This process involves creating a gas hydrate, washing it and then disassociating hydrate into water and gas molecules. The application of this technology results in three process streams: purified water, brine, and gas. The purified water can be discharged or reused for a variety of beneficial purposes and the smaller brine can be disposed of using conventional strategies. The overall objectives of this research are to develop a new treatment method for produced water where it could be purified directly at the wellhead, to determine the effectiveness of hydrate formation for the treatment of produced water with proof of concept laboratory experiments, to design a prototype-scale injector and test it in the laboratory under realistic wellhead conditions, and to demonstrate the technology under field conditions. By treating the water on-site, producers could substantially reduce their surface handling costs and economically remove impurities to a quality that would support beneficial use. Batch bench-scale experiments of the hydrate formation process and research conducted at ORNL

  12. Plant-integrated measurement of greenhouse gas emissions from a municipal wastewater treatment plant.

    PubMed

    Yoshida, Hiroko; Mønster, Jacob; Scheutz, Charlotte

    2014-09-15

    Wastewater treatment plants (WWTPs) contribute to anthropogenic greenhouse gas (GHG) emissions. Due to its spatial and temporal variation in emissions, whole plant characterization of GHG emissions from WWTPs face a number of obstacles. In this study, a tracer dispersion method was applied to quantify plant-integrated, real-time emissions of methane and nitrous oxides. Two mobile cavity ring-down spectroscopy sampling devices were used to record downwind gas concentrations emitted from a municipal WWTP situated in Copenhagen, Denmark. This plant is equipped to remove biological nitrogen and employs anaerobic digestion for sludge stabilization. Over the course of nine measurement campaigns, a wide range of emissions were detected: methane from 4.99 kg h(-1) up to 92.3 kg h(-1) and nitrous oxide from below the detection limit (0.37 kg h(-1)) up to 10.5 kg h(-1). High emissions were observed during periods experiencing operational problems, such as during foaming events in anaerobic digesters and during sub-optimal operation of biological nitrogen removal in the secondary treatment of wastewater. Methane emissions detected during measurement campaigns corresponded to 2.07-32.7% of the methane generated in the plant. As high as 4.27% of nitrogen entering the WWTP was emitted as nitrous oxide under the sub-optimal operation of biological treatment processes. The study shows that the unit process configuration, as well as the operation of the WWTP, determines the rate of GHG emission. The applied plant-integrated emission measurement method could be used to ease the burden of quantifying GHG emissions from WWTPs for reporting purposes and could contribute to the development of more accurate depictions of environmental performance of WWTPs.

  13. Wetland treatment of oil and gas well waste waters. Final report

    SciTech Connect

    Kadlec, R.; Srinivasan, K.

    1995-08-01

    Constructed wetlands are small on-site systems that possess three of the most desirable components of an industrial waste water treatment scheme: low cost, low maintenance and upset resistance. The main objective of the present study is to extend the knowledge base of wetland treatment systems to include processes and substances of particular importance to small, on-site systems receiving oil and gas well wastewaters. A list of the most relevant and comprehensive publications on the design of wetlands for water quality improvement was compiled and critically reviewed. Based on our literature search and conversations with researchers in the private sector, toxic organics such as Phenolics and b-naphthoic acid, (NA), and metals such as CU(II) and CR(VI) were selected as target adsorbates. A total of 90 lysimeters equivalent to a laboratory-scale wetland were designed and built to monitor the uptake and transformation of toxic organics and the immobilization of metal ions. Studies on the uptake of toxic organics such as phenol and b-naphthoic acid (NA) and heavy metals such as Cu(II) and Cr(VI), the latter two singly or as non-stoichiometric mixtures by laboratory-type wetlands (LWs) were conducted. These LWs were designed and built during the first year of this study. A road map and guidelines for a field-scale implementation of a wetland system for the treatment of oil and gas wastewaters have been suggested. Two types of wetlands, surface flow (SF) and sub surface flow (SSF), have been considered, and the relative merits of each configuration have been reviewed.

  14. Greenhouse gas emissions during MSW landfilling in China: influence of waste characteristics and LFG treatment measures.

    PubMed

    Yang, Na; Zhang, Hua; Shao, Li-Ming; Lü, Fan; He, Pin-Jing

    2013-11-15

    Reducing greenhouse gas (GHG) emissions from municipal solid waste (MSW) treatment can be highly cost-effective in terms of GHG mitigation. This study investigated GHG emissions during MSW landfilling in China under four existing scenarios and in terms of seven different categories: waste collection and transportation, landfill management, leachate treatment, fugitive CH4 (FM) emissions, substitution of electricity production, carbon sequestration and N2O and CO emissions. GHG emissions from simple sanitary landfilling technology where no landfill gas (LFG) extraction took place (Scenario 1) were higher (641-998 kg CO2-eq·t(-1)ww) than those from open dump (Scenario 0, 480-734 kg CO2-eq·t(-1)ww). This was due to the strictly anaerobic conditions in Scenario 1. LFG collection and treatment reduced GHG emissions to 448-684 kg CO2-eq·t(-1)ww in Scenario 2 (with LFG flare) and 214-277 kg CO2-eq·t(-1)ww in Scenario 3 (using LFG for electricity production). Amongst the seven categories, FM was the predominant contributor to GHG emissions. Global sensitivity analysis demonstrated that the parameters associated with waste characteristics (i.e. CH4 potential and carbon sequestered faction) and LFG management (i.e. LFG collection efficiency and CH4 oxidation efficiency) were of great importance. A further learning on the MSW in China indicated that water content and dry matter content of food waste were the basic factors affecting GHG emissions. Source separation of food waste, as well as increasing the incineration ratio of mixed collected MSW, could effectively mitigate the overall GHG emissions from landfilling in a specific city. To increase the LFG collection and CH4 oxidation efficiencies could considerably reduce GHG emissions on the landfill site level. While, the improvement in the LFG utilization measures had an insignificant impact as long as the LFG is recovered for energy generation.

  15. Elimination of transmissible spongiform encephalopathy infectivity and decontamination of surgical instruments by using radio-frequency gas-plasma treatment.

    PubMed

    Baxter, H C; Campbell, G A; Whittaker, A G; Jones, A C; Aitken, A; Simpson, A H; Casey, M; Bountiff, L; Gibbard, L; Baxter, R L

    2005-08-01

    It has now been established that transmissible spongiform encephalopathy (TSE) infectivity, which is highly resistant to conventional methods of deactivation, can be transmitted iatrogenically by contaminated stainless steel. It is important that new methods are evaluated for effective removal of protein residues from surgical instruments. Here, radio-frequency (RF) gas-plasma treatment was investigated as a method of removing both the protein debris and TSE infectivity. Stainless-steel spheres contaminated with the 263K strain of scrapie and a variety of used surgical instruments, which had been cleaned by a hospital sterile-services department, were examined both before and after treatment by RF gas plasma, using scanning electron microscopy and energy-dispersive X-ray spectroscopic analysis. Transmission of scrapie from the contaminated spheres was examined in hamsters by the peripheral route of infection. RF gas-plasma treatment effectively removed residual organic residues on reprocessed surgical instruments and gross contamination both from orthopaedic blades and from the experimentally contaminated spheres. In vivo testing showed that RF gas-plasma treatment of scrapie-infected spheres eliminated transmission of infectivity. The infectivity of the TSE agent adsorbed on metal spheres could be removed effectively by gas-plasma cleaning with argon/oxygen mixtures. This treatment can effectively remove 'stubborn' residual contamination on surgical instruments.

  16. Elimination of transmissible spongiform encephalopathy infectivity and decontamination of surgical instruments by using radio-frequency gas-plasma treatment.

    PubMed

    Baxter, H C; Campbell, G A; Whittaker, A G; Jones, A C; Aitken, A; Simpson, A H; Casey, M; Bountiff, L; Gibbard, L; Baxter, R L

    2005-08-01

    It has now been established that transmissible spongiform encephalopathy (TSE) infectivity, which is highly resistant to conventional methods of deactivation, can be transmitted iatrogenically by contaminated stainless steel. It is important that new methods are evaluated for effective removal of protein residues from surgical instruments. Here, radio-frequency (RF) gas-plasma treatment was investigated as a method of removing both the protein debris and TSE infectivity. Stainless-steel spheres contaminated with the 263K strain of scrapie and a variety of used surgical instruments, which had been cleaned by a hospital sterile-services department, were examined both before and after treatment by RF gas plasma, using scanning electron microscopy and energy-dispersive X-ray spectroscopic analysis. Transmission of scrapie from the contaminated spheres was examined in hamsters by the peripheral route of infection. RF gas-plasma treatment effectively removed residual organic residues on reprocessed surgical instruments and gross contamination both from orthopaedic blades and from the experimentally contaminated spheres. In vivo testing showed that RF gas-plasma treatment of scrapie-infected spheres eliminated transmission of infectivity. The infectivity of the TSE agent adsorbed on metal spheres could be removed effectively by gas-plasma cleaning with argon/oxygen mixtures. This treatment can effectively remove 'stubborn' residual contamination on surgical instruments. PMID:16033987

  17. The greenhouse gas and energy balance of different treatment concepts for bio-waste.

    PubMed

    Ortner, Maria E; Müller, Wolfgang; Bockreis, Anke

    2013-10-01

    The greenhouse gas (GHG) and energy performance of bio-waste treatment plants been investigated for three characteristic bio-waste treatment concepts: composting; biological drying for the production of biomass fuel fractions; and anaerobic digestion. Compared with other studies about the environmental impacts of bio-waste management, this study focused on the direct comparison of the latest process concepts and state-of-the-art emission control measures. To enable a comparison, the mass balance and products were modelled for all process concepts assuming the same bio-waste amounts and properties. In addition, the value of compost as a soil improver was included in the evaluation, using straw as a reference system. This aspect has rarely been accounted for in other studies. The study is based on data from operational facilities combined with literature data. The results show that all three concepts contribute to a reduction of GHG emissions and show a positive balance for cumulated energy demand. However, in contrast to other studies, the advantage of anaerobic digestion compared with composting is smaller as a result of accounting for the soil improving properties of compost. Still, anaerobic digestion is the environmentally superior solution. The results are intended to inform decision makers about the relevant aspects of bio-waste treatment regarding the environmental impacts of different bio-waste management strategies.

  18. Design Of A Sorbent/desorbent Unit For Sample Pre-treatment Optimized For QMB Gas Sensors

    NASA Astrophysics Data System (ADS)

    Pennazza, G.; Santonico, M.; Martinelli, E.; Paolesse, R.; Di Natale, C.; Cristina, S.; D'Amico, A.

    2009-05-01

    Sample pre-treatment is a typical procedure in analytical chemistry aimed at improving the performance of analytical systems. In case of gas sensors sample pre-treatment systems are devised to overcome sensors limitations in terms of selectivity and sensitivity. For this purpose, systems based on adsorption and desorption processes driven by temperature conditioning have been illustrated. The involvement of large temperature ranges may pose problems when QMB gas sensors are used. In this work a study of such influences on the overall sensing properties of QMB sensors are illustrated. The results allowed the design of a pret-reatment unit coupled with a QMB gas sensors array optimized to operate in a suitable temperatures range. The performance of the system are illustrated by the partially separation of water vapor in a gas mixture, and by substantial improvement of the signal to noise ratio.

  19. Hindered gas-phase partitioning of trichloroethylene from aqueous cyclodextrin systems: implications for treatment and analysis.

    PubMed

    Kashiyama, N; Boving, T B

    2004-08-15

    Chemically enhanced flushing has shown great promise for attenuating subsurface nonaqueous phase liquid (NAPL) contamination. One particular chemically enhanced remediation technology is cyclodextrin enhanced flushing (CDEF). CDEF has been demonstrated as a viable alternative to conventional and innovative remediation methods. However, the presence of cyclodextrin (CD) in solution complicates the treatment and analysis of volatile organic compounds, such as trichloroethylene (TCE). The principal reason for the complications is the presence of TCE in three compartments instead of two, i.e., the aqueous solution, the vapor phase, and complexed inside the soluble CD molecule. Aqueous TCE-CD systems were examined at various concentration and temperature conditions and their respective Henry's law constants were measured. The presence of CD significantly decreased Henry's law constant of TCE. On the basis of these results, a quantitative model was developed to predict the additional effort that becomes necessary when air-stripping TCE from CDEF flushing solution. The modeling results demonstrate that the presence of CD requires significantly higher gas flow rates or longer residence times of the flushing solution inside an air stripper. Similarly, current gas chromatographic purge-and-trap methods for TCE analysis in CD solution appear to underestimate the aqueous phase TCE concentration if the CD concentration of the sample is not accounted for. Although this model was developed specifically for CD-TCE systems, it is likely that these results have implications for other VOCs and other solubilization enhancing agents, such as surfactants or cosolvents.

  20. Effects of gas atmospheres on poly(lactic acid) film in acrylic acid plasma treatment

    NASA Astrophysics Data System (ADS)

    Zhao, Yun; Fina, Alberto; Venturello, Alberto; Geobaldo, Francesco

    2013-10-01

    Plasma polymerized acrylic acid (AA) coatings were deposited on poly(lactic acid) (PLA) films in various gas atmospheres during the pre-treatment of PLA and the deposition of AA, respectively. Therefore, this work was twofold: the argon pretreated PLA films followed by a deposition in argon were investigated against the mixture of argon and oxygen pretreated ones under the same deposition conditions; the plasma deposition of AA operating in different atmospheres (argon, oxygen and nitrogen) was employed to modify the pretreated PLA in oxygen. Chemical and physical changes on the plasma-treated surfaces were examined using contact angle, X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FE-SEM) and attenuated total reflection infrared (ATR-FTIR) analysis. The results showed that the discharge gas can have a significant influence on the chemical composition of the PLA surfaces: oxygen plasmas introduced oxygen-containing groups in company with surface etching in pretreatment and deposition, while argon discharges was able to achieve much better hydrophilic behavior and high retention ratio of poly(acrylic acid) (PAA) coating before and after washing in water.

  1. Air-lift reactor system for the treatment of waste-gas-containing monochlorobenzene.

    PubMed

    Joshi, Pradnya R; Deshmukh, Sharvari C; Morone, Amruta P; Kanade, Gajanan; Pandey, R A

    2013-01-01

    An air-lift bioreactor (ALR) system, applied for the treatment of waste-gas-containing monochlorobenzene (MCB) was seeded with pure culture of Acinetobacter calcoaceticus, isolated from soil as a starter seed. It was found that MCB was biologically converted to chloride as chloride was mineralized in the ALR. After the built up of the biomass in the ALR, the reactor parameters which have major influence on the removal efficiency and elimination capacity were studied using response surface methodology. The data generated by running the reactor for 150 days at varying conditions were fed to the model with a target to obtain the removal efficiency above 95% and the elimination capacity greater than 60%. The data analysis indicated that inlet loading was the major parameter affecting the elimination capacity and removal efficiency of >95%. The reactor when operated at optimized conditions resulted in enhanced performance of the reactor.

  2. Wetland treatment of oil and gas well wastewaters. Quarterly technical report, August 25--November 24, 1992

    SciTech Connect

    Kadlec, R.H.; Srinivasan, K.R.

    1992-12-24

    In this quarterly report, results of efforts on Tasks 2 and 3 are presented and discussed. Construction of a laboratory-type wetland (green house) has been begun and this undertaking is described in this report. The literature search has shown that clay amendments to wetlands are beginning to be used in Europe for P removal in agricultural drainage systems. The authors have undertaken similar studies on the use of inexpensive amendments to wetlands such as modified-clays and algae to enhance the performance of a constructed wetland for the treatment of oil and gas well wastewaters. The results from these studies are presented and analyzed in this report. Further, the literature search (nominally completed under Task 1) unearthed more recent studies (some unpublished) and a summary is included in this quarterly report.

  3. Gas-Phase Treatment of Technetium in the Vadose Zone at the Hanford Site Central Plateau

    SciTech Connect

    Truex, Michael J.; Szecsody, James E.; Zhong, Lirong; Qafoku, Nikolla

    2014-09-01

    Technetium-99 (Tc-99) is present in the vadose zone of the Hanford Central Plateau and is a concern with respect to the protection of groundwater. The persistence, limited natural attenuation mechanisms, and geochemical behavior of Tc-99 in oxic vadose zone environments must be considered in developing effective alternatives for remediation. This report describes a new in situ geochemical manipulation technique for decreasing Tc-99 mobility using a combination of geochemical Tc-99 reduction with hydrogen sulfide gas and induced sediment mineral dissolution with ammonia vapor, which create conditions for deposition of stable precipitates that decrease the mobility of Tc-99. Laboratory experiments were conducted to examine changes in Tc-99 mobility in vadose zone sediment samples to evaluate the effectiveness of the treatment under a variety of operational and sediment conditions.

  4. Effect of water treatment chemicals on limestone/sulfur dioxide reaction in flue gas desulfurization systems

    SciTech Connect

    Dille, E.R.; Gaikwad, R.P.

    1994-12-31

    A simple laboratory test has been developed which simulates the reaction between limestone/water and sulfur dioxide in flue gas desulfurization systems. By adding various chemicals, in differing concentrations, to the limestone/water mixture, the quantitative impact on the sulfur dioxide/limestone reaction can be qualified and quantified. This paper will present the impact of several water treatment chemicals on the reaction of limestone and sulfur dioxide. An attempt has been made to predict the effect through mathematical correlations. All of the additive chemicals tend to decrease the rate of dissolution of limestone to various degrees. Some of the chemicals retard crystal growth thus adversely impacting solids separation in the thickener. The physical appearance of the crystal growth retarded limestone absorber slurry approaches a colloidal suspension.

  5. Recycling of blast furnace sludge by briquetting with starch binder: Waste gas from thermal treatment utilizable as a fuel.

    PubMed

    Drobíková, Klára; Plachá, Daniela; Motyka, Oldřich; Gabor, Roman; Kutláková, Kateřina Mamulová; Vallová, Silvie; Seidlerová, Jana

    2016-02-01

    Steel plants generate significant amounts of wastes such as sludge, slag, and dust. Blast furnace sludge is a fine-grained waste characterized as hazardous and affecting the environment negatively. Briquetting is one of the possible ways of recycling of this waste while the formed briquettes serve as a feed material to the blast furnace. Several binders, both organic and inorganic, had been assessed, however, only the solid product had been analysed. The aim of this study was to assess the possibilities of briquetting using commonly available laundry starch as a binder while evaluating the possible utilization of the waste gas originating from the thermal treatment of the briquettes. Briquettes (100g) were formed with the admixture of starch (UNIPRET) and their mechanical properties were analysed. Consequently, they were subjected to thermal treatment of 900, 1000 and 1100°C with retention period of 40min during which was the waste gas collected and its content analysed using gas chromatography. Dependency of the concentration of the compounds forming the waste gas on the temperature used was determined using Principal component analysis (PCA) and correlation matrix. Starch was found to be a very good binder and reduction agent, it was confirmed that metallic iron was formed during the thermal treatment. Approximately 20l of waste gas was obtained from the treatment of one briquette; main compounds were methane and hydrogen rendering the waste gas utilizable as a fuel while the greatest yield was during the lowest temperatures. Preparation of blast furnace sludge briquettes using starch as a binder and their thermal treatment represents a suitable method for recycling of this type of metallurgical waste. Moreover, the composition of the resulting gas is favourable for its use as a fuel. PMID:26684056

  6. Recycling of blast furnace sludge by briquetting with starch binder: Waste gas from thermal treatment utilizable as a fuel.

    PubMed

    Drobíková, Klára; Plachá, Daniela; Motyka, Oldřich; Gabor, Roman; Kutláková, Kateřina Mamulová; Vallová, Silvie; Seidlerová, Jana

    2016-02-01

    Steel plants generate significant amounts of wastes such as sludge, slag, and dust. Blast furnace sludge is a fine-grained waste characterized as hazardous and affecting the environment negatively. Briquetting is one of the possible ways of recycling of this waste while the formed briquettes serve as a feed material to the blast furnace. Several binders, both organic and inorganic, had been assessed, however, only the solid product had been analysed. The aim of this study was to assess the possibilities of briquetting using commonly available laundry starch as a binder while evaluating the possible utilization of the waste gas originating from the thermal treatment of the briquettes. Briquettes (100g) were formed with the admixture of starch (UNIPRET) and their mechanical properties were analysed. Consequently, they were subjected to thermal treatment of 900, 1000 and 1100°C with retention period of 40min during which was the waste gas collected and its content analysed using gas chromatography. Dependency of the concentration of the compounds forming the waste gas on the temperature used was determined using Principal component analysis (PCA) and correlation matrix. Starch was found to be a very good binder and reduction agent, it was confirmed that metallic iron was formed during the thermal treatment. Approximately 20l of waste gas was obtained from the treatment of one briquette; main compounds were methane and hydrogen rendering the waste gas utilizable as a fuel while the greatest yield was during the lowest temperatures. Preparation of blast furnace sludge briquettes using starch as a binder and their thermal treatment represents a suitable method for recycling of this type of metallurgical waste. Moreover, the composition of the resulting gas is favourable for its use as a fuel.

  7. Combination treatment of chlorine dioxide gas and aerosolized sanitizer for inactivating foodborne pathogens on spinach leaves and tomatoes.

    PubMed

    Park, Sang-Hyun; Kang, Dong-Hyun

    2015-08-17

    The objective of this study was to evaluate the antimicrobial effect of chlorine dioxide (ClO2) gas and aerosolized sanitizer, when applied alone or in combination, on the survival of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes inoculated onto spinach leaves and tomato surfaces. Spinach leaves and tomatoes were inoculated with a cocktail of three strains each of the three foodborne pathogens. ClO2 gas (5 or 10 ppmv) and aerosolized peracetic acid (PAA) (80 ppm) were applied alone or in combination for 20 min. Exposure to 10 ppmv of ClO2 gas for 20 min resulted in 3.4, 3.3, and 3.4 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes on spinach leaves, respectively. Treatment with 80 ppm of aerosolized PAA for 20 min caused 2.3, 1.9, and 0.8 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. Combined treatment of ClO2 gas (10 ppmv) and aerosolized PAA (80 ppm) for 20 min caused 5.4, 5.1, and 4.1 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. E. coli O157:H7, S. Typhimurium, and L. monocytogenes on tomatoes experienced similar reduction patterns to those on spinach leaves. As treatment time increased, most combinations of ClO2 gas and aerosolized PAA showed additive effects in the inactivation of the three pathogens. Combined treatment of ClO2 gas and aerosolized PAA produced injured cells of three pathogens on spinach leaves while generally did not produce injured cells of these pathogens on tomatoes. Combined treatment of ClO2 gas (10 ppmv) and aerosolized PAA (80 ppm) did not significantly (p>0.05) affect the color and texture of samples during 7 days of storage.

  8. Combination treatment of chlorine dioxide gas and aerosolized sanitizer for inactivating foodborne pathogens on spinach leaves and tomatoes.

    PubMed

    Park, Sang-Hyun; Kang, Dong-Hyun

    2015-08-17

    The objective of this study was to evaluate the antimicrobial effect of chlorine dioxide (ClO2) gas and aerosolized sanitizer, when applied alone or in combination, on the survival of Escherichia coli O157:H7, Salmonella Typhimurium, and Listeria monocytogenes inoculated onto spinach leaves and tomato surfaces. Spinach leaves and tomatoes were inoculated with a cocktail of three strains each of the three foodborne pathogens. ClO2 gas (5 or 10 ppmv) and aerosolized peracetic acid (PAA) (80 ppm) were applied alone or in combination for 20 min. Exposure to 10 ppmv of ClO2 gas for 20 min resulted in 3.4, 3.3, and 3.4 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes on spinach leaves, respectively. Treatment with 80 ppm of aerosolized PAA for 20 min caused 2.3, 1.9, and 0.8 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. Combined treatment of ClO2 gas (10 ppmv) and aerosolized PAA (80 ppm) for 20 min caused 5.4, 5.1, and 4.1 log reductions of E. coli O157:H7, S. Typhimurium, and L. monocytogenes, respectively. E. coli O157:H7, S. Typhimurium, and L. monocytogenes on tomatoes experienced similar reduction patterns to those on spinach leaves. As treatment time increased, most combinations of ClO2 gas and aerosolized PAA showed additive effects in the inactivation of the three pathogens. Combined treatment of ClO2 gas and aerosolized PAA produced injured cells of three pathogens on spinach leaves while generally did not produce injured cells of these pathogens on tomatoes. Combined treatment of ClO2 gas (10 ppmv) and aerosolized PAA (80 ppm) did not significantly (p>0.05) affect the color and texture of samples during 7 days of storage. PMID:26001524

  9. Greenhouse gas emissions from landfill leachate treatment plants: A comparison of young and aged landfill

    SciTech Connect

    Wang, Xiaojun; Jia, Mingsheng; Chen, Xiaohai; Xu, Ying; Lin, Xiangyu; Kao, Chih Ming; Chen, Shaohua

    2014-07-15

    Highlights: • Young and aged leachate works accounted for 89.1% and 10.9% of 33.35 Gg CO{sub 2} yr{sup −1}. • Fresh leachate owned extremely low ORP and high organic matter content. • Strong CH{sub 4} emissions occurred in the fresh leachate ponds, but small in the aged. • N{sub 2}O emissions became dominant in the treatment units of both systems. • 8.45–11.9% of nitrogen was removed as the form of N{sub 2}O under steady-state. - Abstract: With limited assessment, leachate treatment of a specified landfill is considered to be a significant source of greenhouse gas (GHG) emissions. In our study, the cumulative GHG emitted from the storage ponds and process configurations that manage fresh or aged landfill leachate were investigated. Our results showed that strong CH{sub 4} emissions were observed from the fresh leachate storage pond, with the fluxes values (2219–26,489 mg C m{sup −2} h{sup −1}) extremely higher than those of N{sub 2}O (0.028–0.41 mg N m{sup −2} h{sup −1}). In contrast, the emission values for both CH{sub 4} and N{sub 2}O were low for the aged leachate tank. N{sub 2}O emissions became dominant once the leachate entered the treatment plants of both systems, accounting for 8–12% of the removal of N-species gases. Per capita, the N{sub 2}O emission based on both leachate treatment systems was estimated to be 7.99 g N{sub 2}O–N capita{sup −1} yr{sup −1}. An increase of 80% in N{sub 2}O emissions was observed when the bioreactor pH decreased by approximately 1 pH unit. The vast majority of carbon was removed in the form of CO{sub 2}, with a small portion as CH{sub 4} (<0.3%) during both treatment processes. The cumulative GHG emissions for fresh leachate storage ponds, fresh leachate treatment system and aged leachate treatment system were 19.10, 10.62 and 3.63 Gg CO{sub 2} eq yr{sup −1}, respectively, for a total that could be transformed to 9.09 kg CO{sub 2} eq capita{sup −1} yr{sup −1}.

  10. Plasma-chemical treatment of hydrogen sulfide in natural gas processing. Final report, May 1991--December 1992

    SciTech Connect

    Harkness, J.B.L.; Doctor, R.D.

    1993-05-01

    A new process for the treatment of hydrogen sulfide waste that uses microwave plasma-chemical technology has been under development in Russia and the United States. Whereas the present waste-treatment technology, at best, only recovers sulfur, this novel process recovers both hydrogen and sulfur by dissociating hydrogen sulfide in a plasma by means of a microwave or radio-frequency reactor. A research project has been undertaken to determine the suitability of the plasma process in natural gas processing applications. The experiments tested acid-gas compositions with 30--65% carbon dioxide, 0--7% water, and 0--0.2% of a standard mixture of pipeline gas. The balance gas in all cases was hydrogen sulfide. The reactor pressure for the experiments was 50 torr, and the microwave power was 1.0 kW. Conversions of hydrogen sulfide ranged from 80 to 100%, while 35--50% of the carbon dioxide was converted to carbon monoxide. This conversion of carbon dioxide resulted in a loss of hydrogen production and an energy loss from a hydrogen sulfide waste-treatment perspective. Tests of a direct natural gas treatment concept showed that hydrocarbon losses were unacceptably high; consequently, the concept would not be economically viable.

  11. GIS based location optimization for mobile produced water treatment facilities in shale gas operations

    NASA Astrophysics Data System (ADS)

    Kitwadkar, Amol Hanmant

    Over 60% of the nation's total energy is supplied by oil and natural gas together and this demand for energy will continue to grow in the future (Radler et al. 2012). The growing demand is pushing the exploration and exploitation of onshore oil and natural gas reservoirs. Hydraulic fracturing has proven to not only create jobs and achieve economic growth, but also has proven to exert a lot of stress on natural resources---such as water. As water is one of the most important factors in the world of hydraulic fracturing, proper fluids management during the development of a field of operation is perhaps the key element to address a lot of these issues. Almost 30% of the water used during hydraulic fracturing comes out of the well in the form of flowback water during the first month after the well is fractured (Bai et. al. 2012). Handling this large amount of water coming out of the newly fractured wells is one of the major issues as the volume of the water after this period drops off and remains constant for a long time (Bai et. al. 2012) and permanent facilities can be constructed to take care of the water over a longer period. This paper illustrates development of a GIS based tool for optimizing the location of a mobile produced water treatment facility while development is still occurring. A methodology was developed based on a multi criteria decision analysis (MCDA) to optimize the location of the mobile treatment facilities. The criteria for MCDA include well density, ease of access (from roads considering truck hauls) and piping minimization if piping is used and water volume produced. The area of study is 72 square miles east of Greeley, CO in the Wattenberg Field in northeastern Colorado that will be developed for oil and gas production starting in the year 2014. A quarterly analysis is done so that we can observe the effect of future development plans and current circumstances on the location as we move from quarter to quarter. This will help the operators to

  12. Options to reduce greenhouse gas emissions during wastewater treatment for agricultural use.

    PubMed

    Fine, Pinchas; Hadas, Efrat

    2012-02-01

    Treatment of primarily-domestic sewage wastewater involves on-site greenhouse gas (GHG) emissions due to energy inputs, organic matter degradation and biological nutrient removal (BNR). BNR causes both direct emissions and loss of fertilizer value, thus eliminating possible reduction of emissions caused by fertilizer manufacture. In this study, we estimated on-site GHG emissions under different treatment scenarios, and present options for emission reduction by changing treatment methods, avoiding BNR and by recovering energy from biogas. Given a typical Israeli wastewater strength (1050mg CODl(-1)), the direct on-site GHG emissions due to energy use were estimated at 1618 and 2102g CO(2)-eq m(-3), respectively, at intermediate and tertiary treatment levels. A potential reduction of approximately 23-55% in GHG emissions could be achieved by fertilizer preservation and VS conversion to biogas. Wastewater fertilizers constituted a GHG abatement potential of 342g CO(2)-eq m(-3). The residual component that remained in the wastewater effluent following intermediate (oxidation ponds) and enhanced (mechanical-biological) treatments was 304-254g CO(2)-eq m(-3) and 65-34g CO(2)-eq m(-3), respectively. Raw sludge constituted approximately 47% of the overall wastewater fertilizers load with an abatement potential of 150g CO(2)-eq m(-3) (385kg CO(2)-eq dry tonne(-1)). Inasmuch as anaerobic digestion reduced it to 63g CO(2)-eq m(-3) (261kg CO(2)-eq dry tonne(-1)), the GHG abatement gained through renewable biogas energy (approx. 428g CO(2)-eq m(-3)) favored digestion. However, sludge composting reduced the fertilizer value to 17g CO(2)-eq m(-3) (121kg CO(2)-eq dry tonne(-1)) or less (if emissions, off-site inputs and actual phytoavailability were considered). Taking Israel as an example, fully exploiting the wastewater derived GHG abatement potential could reduce the State overall GHG emissions by almost 1%. This demonstrates the possibility of optional carbon credits which

  13. Pilot plant experience in electron-beam treatment of iron-ore sintering flue gas and its application to coal boiler flue gas cleanup

    NASA Astrophysics Data System (ADS)

    Kawamura, K.; Shui, V. H.

    The peresent development status of the electron-beam flue gas treatment process, which is a dry process capable of removing SOx and NOx simultaneously, is described. The most advanced demonstration of this process was accomplished with a pilot plant in Japan where the maximum gas flow rate of 10,000 Nm 3/h of an iron-ore sintering machine flue gas was successfully treated. The byproduct produced in this process is collected as a dry powder which is a mixture of ammonia sulfate and ammonium nitrate and is salable as a fertilizer or a fertilizer component. A preliminary economic projection showed that this process costs less than the lime scrubber which removes SOx but does not remove NOx. Tests using simulated coal combustion gases suggest that this process will be applicable to coal-fired boiler flue gas treatment as well. However, test on actual coal-fired flue gases are still required for commercial application decisions. A process development unit program consisting of the design, construction and testing of actual coal-fired power station flue gases is underway in the U.S.A. The design and engineering of the test plant is far advanced and the construction phase will be launched in the very near future.

  14. Greenhouse gas emissions during MSW landfilling in China: influence of waste characteristics and LFG treatment measures.

    PubMed

    Yang, Na; Zhang, Hua; Shao, Li-Ming; Lü, Fan; He, Pin-Jing

    2013-11-15

    Reducing greenhouse gas (GHG) emissions from municipal solid waste (MSW) treatment can be highly cost-effective in terms of GHG mitigation. This study investigated GHG emissions during MSW landfilling in China under four existing scenarios and in terms of seven different categories: waste collection and transportation, landfill management, leachate treatment, fugitive CH4 (FM) emissions, substitution of electricity production, carbon sequestration and N2O and CO emissions. GHG emissions from simple sanitary landfilling technology where no landfill gas (LFG) extraction took place (Scenario 1) were higher (641-998 kg CO2-eq·t(-1)ww) than those from open dump (Scenario 0, 480-734 kg CO2-eq·t(-1)ww). This was due to the strictly anaerobic conditions in Scenario 1. LFG collection and treatment reduced GHG emissions to 448-684 kg CO2-eq·t(-1)ww in Scenario 2 (with LFG flare) and 214-277 kg CO2-eq·t(-1)ww in Scenario 3 (using LFG for electricity production). Amongst the seven categories, FM was the predominant contributor to GHG emissions. Global sensitivity analysis demonstrated that the parameters associated with waste characteristics (i.e. CH4 potential and carbon sequestered faction) and LFG management (i.e. LFG collection efficiency and CH4 oxidation efficiency) were of great importance. A further learning on the MSW in China indicated that water content and dry matter content of food waste were the basic factors affecting GHG emissions. Source separation of food waste, as well as increasing the incineration ratio of mixed collected MSW, could effectively mitigate the overall GHG emissions from landfilling in a specific city. To increase the LFG collection and CH4 oxidation efficiencies could considerably reduce GHG emissions on the landfill site level. While, the improvement in the LFG utilization measures had an insignificant impact as long as the LFG is recovered for energy generation. PMID:24018116

  15. Saline gas-produced waters treatment with macrophytes in a hydroponic system. Final report, July 1, 1991-December 31, 1992

    SciTech Connect

    Jewell, W.J.; Albright, L.D.; Cummings, R.J.; Hicks, E.E.; Nock, T.D.

    1993-06-01

    A review of potential pollution problems of natural gas produced waters emphasized that present regulations do not adversely affect gas production, but future changes may be a concern (Fillo et al.). Also, the economics of the present treatment and disposal practices are becoming unacceptably high. Thus, new and more effective methods of treating and disposing of produced waters should be sought. A hydroponic system has been developed at Cornell University and piloted on domestic sewage partly with support from the Gas Research Institute, the U.S. Department of Energy (SERI), USEPA and New York State Energy Research and Development Authority (Jewell et al.). The hydroponic plant system is referred to as the 'Nutrient Film Technique' (NFT). The general goal of the project is to conduct a preliminary study to determine the feasibility of developing a biological treatment system capable of removing organic and inorganic pollutants from highly saline waters while minimizing the effluent volume by enhanced evapotranspiration.

  16. A COMPARISON OF LIQUID AND GAS-PHASE PHOTOOXIDATION TREATMENT OF METHYL TERTIARY BUTYL ETHER: SYNTHETIC AND FIELD SAMPLES

    EPA Science Inventory

    The feasibility of photo-oxidation treatment of metyl tert-butyl either (MTBE) in water was investigated using two systems, 1) a slurry falling film photo-reactor, and 2) an integrated air-stripping with gas phase photooxidation system. MTBE-contaminated synthetic water and field...

  17. Final Report on Testing of Off-Gas Treatment Technologies for Abatement of Atmospheric Emissions of Chlorinated Volatile Organic Compounds

    SciTech Connect

    Jarosch, T.R.; Haselow, J.S.; Rossabi, J.; Burdick, S.A.; Raymond, R.; Young, J.E.; Lombard, K.H.

    1995-01-23

    The purpose of this report is to summarize the results of the program for off-gas treatment of atmospheric emissions of chlorinated volatile organic compounds (CVOCs), in particular trichloroethylene (TCE) and perchloroethylene (PCE). This program was funded through the Department of Energy Office of Technology Development`s VOC`s in Non-Arid Soils Integrated Demonstration (VNID). The off-gas treatment program was initiated after testing of in-situ air stripping with horizontal wells was completed (Looney et al., 1991). That successful test expectedly produced atmospheric emissions of CVOCs that were unabated. It was decided after that test that an off-gas treatment is an integral portion of remediation of CVOC contamination in groundwater and soil but also because several technologies were being developed across the United States to mitigate CVOC emissions. A single platform for testing off-gas treatment technologies would facilitate cost effective evaluation of the emerging technologies. Another motivation for the program is that many CVOCs will be regulated under the Clean Air Act Amendments of 1990 and are already regulated by many state regulatory programs. Additionally, compounds such as TCE and PCE are pervasive subsurface environmental contaminants, and, as a result, a small improvement in terms of abatement efficiency or cost will significantly reduce CVOC discharges to the environment as well as costs to United States government and industry.

  18. Systematic selection of off-gas treatment at the Savannah River Site

    SciTech Connect

    McKillip, S.T.; Rehder, T.E.

    1992-05-01

    At the Savannah River Site (SRS), from 1958--1985, effluent waste from the reactor fuel and target rod fabrication area (M-Area) was discharged to a settling basin. In 1981, monitoring wells detected groundwater contamination, specifically trichloroethylene and tetrachloroethylene, in the immediate vicinity of the basin. Under the auspices of Resource Conservation and Recovery Act (RCRA) the M-Area contamination must be addressed by a corrective action program until the volatile organic compound (VOC) concentrations reach Drinking Water Standards. This was initiated in 1985 with startup of a full-scale pump-and-treat air stripper system. Recently, remediation efforts have focused on vacuum extraction to treat vadose zone contamination not addressed by the original recovery wells, and additional pump-and-treat systems to achieve hydraulic control of the plume. Regulatory requirements allowed for discharge of VOCs to the atmosphere when the original remediation system was installed; however, 1990 amendments to the Clean Air Act will eventually require treatment of VOC contaminated air prior to discharge. This has ramifications to systems currently being design, as well as the existing systems. In response to the 1990 Clean Air Act amendments, SRS initiated a study to assess commercially available off-gas treatment technologies. These included carbon adsorption, thermal incineration, catalytic oxidation, absorption, condensation, and UV/peroxide destruction, and xenon flashlamp. Criteria used to evaluate the technologies were the thirty (30) year life cycle cost, permitting considerations, and manpower requirements. The study concluded that catalytic oxidation provided the most desirable combination of these elements.

  19. Systematic selection of off-gas treatment at the Savannah River Site

    SciTech Connect

    McKillip, S.T.; Rehder, T.E.

    1992-01-01

    At the Savannah River Site (SRS), from 1958--1985, effluent waste from the reactor fuel and target rod fabrication area (M-Area) was discharged to a settling basin. In 1981, monitoring wells detected groundwater contamination, specifically trichloroethylene and tetrachloroethylene, in the immediate vicinity of the basin. Under the auspices of Resource Conservation and Recovery Act (RCRA) the M-Area contamination must be addressed by a corrective action program until the volatile organic compound (VOC) concentrations reach Drinking Water Standards. This was initiated in 1985 with startup of a full-scale pump-and-treat air stripper system. Recently, remediation efforts have focused on vacuum extraction to treat vadose zone contamination not addressed by the original recovery wells, and additional pump-and-treat systems to achieve hydraulic control of the plume. Regulatory requirements allowed for discharge of VOCs to the atmosphere when the original remediation system was installed; however, 1990 amendments to the Clean Air Act will eventually require treatment of VOC contaminated air prior to discharge. This has ramifications to systems currently being design, as well as the existing systems. In response to the 1990 Clean Air Act amendments, SRS initiated a study to assess commercially available off-gas treatment technologies. These included carbon adsorption, thermal incineration, catalytic oxidation, absorption, condensation, and UV/peroxide destruction, and xenon flashlamp. Criteria used to evaluate the technologies were the thirty (30) year life cycle cost, permitting considerations, and manpower requirements. The study concluded that catalytic oxidation provided the most desirable combination of these elements.

  20. Topical Cyclosporine A for Treatment of Dry Eye Due to Chronic Mustard Gas Injury

    PubMed Central

    Jadidi, Khosrow; Panahi, Yunes; Ebrahimi, Ali; Mafi, Mostafa; Nejat, Farhad; Sahebkar, Amirhossein

    2014-01-01

    Purpose: To evaluate the efficacy of topical cyclosporine A (tCsA) for treatment of dry eye disease in patients suffering from chronic ocular complications of mustard gas (MG) injury. Methods: This interventional case series included patients with MG injury suffering from severe dry eye despite receiving artificial tears and punctal plugs. Patients were administered tCsA 0.05% twice daily for 3 months. Severity of the condition was evaluated by measuring tear osmolarity, ocular surface disease index (OSDI), tear break-up time (TBUT), and Schirmer's test at baseline and at the end of study. Results: A total of 34 patients with chronic MG injury and mean age of 47.1 ± 6.5 years were studied. Compared to baseline values, tear osmolarity (301.7 ± 11.5 vs. 286.3 ± 7.9 mOsmol/L, P < 0.001) and OSDI (47.5 ± 7.2 vs. 42.7 ± 7.1, P < 0.001) were significantly improved. Likewise, Schirmer's test (4.6 ± 1.3 vs. 5 ± 1.3 mm, P < 0.001) and TBUT (1.9 ± 1.4 vs. 2.7 ± 1.5 s, P < 0.001) also significantly recovered at the end of the study. Conclusion: TCsA 0.05% reduces tear osmolarity and improves dry eye symptoms and can serve as an efficacious treatment for ocular complications in patients with chronic MG injury. PMID:25709764

  1. Including greenhouse gas emissions during benchmarking of wastewater treatment plant control strategies.

    PubMed

    Flores-Alsina, Xavier; Corominas, Lluís; Snip, Laura; Vanrolleghem, Peter A

    2011-10-15

    The main objective of this paper is to demonstrate how greenhouse gas (GHG) emissions can be quantified during the evaluation of control strategies in wastewater treatment plants (WWTP). A modified version of the IWA Benchmark Simulation Model No 2 (BSM2G) is hereby used as a simulation case study. Thus, the traditional effluent quality index (EQI), operational cost index (OCI) and time in violation (TIV) used to evaluate control strategies in WWTP are complemented with a new dimension dealing with GHG emissions. The proposed approach is based on a set of comprehensive models that estimate all potential on-site and off-site sources of GHG emissions. The case study investigates the overall performance of several control strategies and demonstrates that substantial reductions in effluent pollution, operating costs and GHG emissions can be achieved when automatic control is implemented. Furthermore, the study is complemented with a scenario analysis that examines the role of i) the dissolved oxygen (DO) set-point, ii) the sludge retention time (SRT) and iii) the organic carbon/nitrogen ratio (COD/N) as promoters of GHG emissions. The results of this study show the potential mechanisms that promote the formation of CO2, CH4 and N2O when different operational strategies are implemented, the existing synergies and trade-offs amongst the EQI, the OCI and TIV criteria and finally the need to reach a compromise solution to achieve an optimal plant performance.

  2. Continuous biological waste gas treatment in stirred trickle-bed reactor with discontinuous removal of biomass

    SciTech Connect

    Laurenzis, A.; Heits, H.; Wuebker, S.M.; Heinze, U.; Friedrich, C.; Werner, U.

    1998-02-20

    A new reactor for biological waste gas treatment was developed to eliminate continuous solvents from waste gases. A trickle-bed reactor was chosen with discontinuous movement of the packed bed and intermittent percolation. The reactor was operated with toluene as the solvent and an optimum average biomass concentration of between 5 and 30 kg dry cell weight per cubic meter packed bed (m{sub pb}{sup 3}). This biomass concentration resulted in a high volumetric degradation rate. Reduction of surplus biomass by stirring and trickling caused a prolonged service life and prevented clogging of the trickle bed and a pressure drop increase. The pressure drop after biomass reduction was almost identical to the theoretical pressure drop as calculated for the irregular packed bed without biomass. The reduction in biomass and intermittent percolation of mineral medium resulted in high volumetric degradation rates of about 100 g of toluene m{sub pb}{sup {minus}3} h{sup {minus}1} at a load of 150 g of toluene m{sub pb}{sup {minus}3} h{sup {minus}1}. Such a removal rate with a trickle-bed reactor was not reported before.

  3. Photoluminescence and hydrogen gas-sensing properties of titanium dioxide nanostructures synthesized by hydrothermal treatments.

    PubMed

    Sikhwivhilu, Lucky M; Mpelane, Siyasanga; Mwakikunga, Bonex W; Ray, Suprakas Sinha

    2012-03-01

    Titanium dioxide (TiO(2)) nanostructures were synthesized by microwave-assisted and conventionally heated hydrothermal treatment of TiO(2) powder. The tubular structures were converted to a rodlike shape by sintering the samples at various temperatures in air for 3 h. This was accompanied by phase transformation largely influenced by the method of synthesis and the mode of heating. The X-ray diffraction results are in agreement with the structural transformation indicating the gradual changes in the phase and crystallinity of the as prepared samples. The tubular structure is found to collapse at high temperature. UV-vis-IR spectroscopic results suggest that nanorods tend to absorb photons of higher energy (λ = 280 nm) than nanotubes (λ = 300 nm) but emit photons with lower energy than nanotubes. It was found that the nanotubes have a sharper photoluminance emission line at 340 nm that is absent in the nanorods. We also found that nanotubes have higher efficiency, lower threshold sensing temperature, longer response time, and shorter recovery time for hydrogen gas sensing than nanorods. PMID:22352872

  4. Investigations of Biofilm-Forming Bacterial Cells by Atomic Force Microscopy Prior to and Following Treatment from Gas Discharge Plasmas

    NASA Astrophysics Data System (ADS)

    Vandervoort, K. G.; Joaquin, J. C.; Kwan, C.; Bray, J. D.; Torrico, R.; Abramzon, N.; Brelles-Marino, G.

    2007-03-01

    We present investigations of biofilm-forming bacteria before and after treatment from gas discharge plasmas. Gas discharge plasmas represent a way to inactivate bacteria under conditions where conventional disinfection methods are often ineffective. These conditions involve bacteria in biofilm communities, where cooperative interactions between cells make organisms less susceptible to standard killing methods. Rhizobium gallicum and Chromobacterium violaceum were imaged before and after plasma treatment using an atomic force microscope (AFM). In addition, cell wall elasticity was studied by measuring force distance curves as the AFM tip was pressed into the cell surface. Results for cell surface morphology and micromechanical properties for plasma treatments lasting from 5 to 60 minutes were obtained and will be presented.

  5. Laboratory Evaporation Testing Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    SciTech Connect

    Adamson, Duane J.; Nash, Charles A.; McCabe, Daniel J.; Crawford, Charles L.; Wilmarth, William R.

    2014-01-27

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream, LAW Off-Gas Condensate, from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of canistered glass waste forms. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to be within acceptable concentration ranges in the LAW glass. Diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task examines the impact of potential future disposition of this stream in the Hanford tank farms, and investigates auxiliary evaporation to enable another disposition path. Unless an auxiliary evaporator is used, returning the stream to the tank farms would require evaporation in the 242-A evaporator. This stream is expected to be unusual because it will be very high in corrosive species that are volatile in the melter

  6. Impact of mine wastewaters on greenhouse gas emissions from northern peatlands used for mine water treatment

    NASA Astrophysics Data System (ADS)

    Palmer, Katharina; Ronkanen, Anna-Kaisa; Klöve, Björn; Hynynen, Jenna; Maljanen, Marja

    2015-04-01

    The amount of wastewaters generated during mining operations is increasing along with the increasing number of operation mines, which poses great challenges for mine water management and purification. Mine wastewaters contain high concentrations of nitrogen compounds such as nitrate (NO3-) and ammonium (NH4+) originating from remnant explosives as well as sulfate (SO42-) originating from the oxidation of sulfidic ores. At a mine site in Finnish Lapland, two natural peatlands have been used for cost-effective passive wastewater treatment. One peatland have been used for the treatment of drainage waters (TP 1), while the other has been used for the treatment of process-based wastewaters (TP 4). In this study, the impact of mine water derived nitrogen compounds as well as SO42- on the emission of the potent greenhouse gases methane (CH4) and nitrous oxide (N2O) from those treatment peatlands was investigated. Contaminant concentrations in the input and output waters of the treatment peatlands were monitored which allowed for the calculation of contaminant-specific retention efficiencies. Treatment peatlands showed generally good retention efficiencies for metals and metalloids (e.g. nickel, arsenic, antimony, up to 98% reduction in concentration) with rather low input-concentrations (i.e., in the μg/l-range). On the other hand, retention of contaminants with high input-concentrations (i.e., in mg/l-range) such as NO3-, NH4+ and SO42- was much lower (4-41%, 30-60% and -42-30%, respectively), indicating the limited capability of the treatment peatlands to cope with such high input concentrations. NO3- and NH4+ concentrations were determined in surface and pore water from TP 4 in July 2013 as well as in surface water from TP 1 and TP 4 in October 2013. Up to 720 μM NO3- and up to 600 μM NH4+ were detected in surface water of TP 4 in July 2013. NO3- and NH4+ concentrations in surface waters were highest near the mine wastewater distribution ditch and decreased with

  7. A pilot study for the extraction and treatment of groundwater from a manufactured gas plant site. Final report

    SciTech Connect

    1997-12-01

    This report describes a pilot study involving treatment of contaminated groundwater at a former manufactured gas plant site on the eastern seaboard of the US. The work was performed in order to provide the design basis for a full-scale groundwater extraction and treatment system at the site, as well as to develop a generic approach to selection of groundwater treatment sequences at other MGP sites. It included three main components: hydrogeologic investigations, bench-scale treatability studies, and pilot-scale treatability studies. Technologies evaluated in bench-scale work included gravity settling, filtration, and dissolved air flotation (DAF) for primary treatment of nonaqueous phase materials; biological degradation, air stripping, and carbon adsorption for secondary treatment of dissolved organics; and carbon adsorption as tertiary treatment of remaining dissolved contaminants. Pilot-scale studies focused on collecting system performance data fore three distinct levels of contamination. Two treatment trains were evaluated. One consisted of DAF, fluidized-bed biotreatment, and filtration plus carbon adsorption; the other used the same steps except to substitute air stripping for fluidized bed treatment. The final effluents produced by both treatment sequences were similar and demonstrated complete treatment of the groundwater. Besides detailing system design and performance for the treatability studies, the report includes an analysis of groundwater treatment applications to MGP sites in general, including a discussion of capital and operating costs.

  8. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) The contract was signed on August 20, 2000. Little work has been performed other than preliminary planning to get the project underway.

  9. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-04-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: Continued coordinating the final selection of candidates and field implementation with Oneok. Oneok plans on performing the operations early in 2003.

  10. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Continued coordinating the final selection of candidates and field implementation with Oneok. Oneok plans on performing the operations early in 2003.

  11. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Began preparing final project report, less the field implementation component. (2) Coordinated the final selection of candidates and field implementation with Oneok.

  12. Application of the biological granular activated carbon fluidized bed reactor process for gas industry waste treatment. Topical report, January 1991-December 1992

    SciTech Connect

    Wagner, D.; Sunday, A.; Hickey, R.F.

    1993-06-01

    The research and development work is focused on evaluating the applicability of using the biological granular activated carbon-fluidized bed reactor (GAC-FBR) for helping to solve gas industry waste treatment needs. The specific goals are to use and modify the GAC-FBR process, as needed, for (1) remediation of groundwater contaminated by gas industry operations, and (2) treatment of gas production and exploration waters.

  13. Laboratory optimization tests of technetium decontamination of Hanford Waste Treatment Plant low activity waste melter off-gas condensate simulant

    SciTech Connect

    Taylor-Pashow, Kathryn M.L.; McCabe, Daniel J.

    2015-11-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable simplified operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste.

  14. Analytical methods and monitoring system for E-beam flue gas treatment process

    NASA Astrophysics Data System (ADS)

    Licki, J.; Chmielewski, A. G.; Iller, E.; Zakrzewska-Trznadel, G.; Tokunaga, O.; Hashimoto, S.

    1998-06-01

    The results of reliable and precise measurement of gas composition in different key points of e-beam installation are necessary for its proper operation and control. Only the composition of flue gas coming into installation is adequate to composition of flue gas emitted from coal-fired boiler. At other points of e-b installation the gas composition is strongly modified by process conditions therefore specific measuring system (sampling and conditioning system and set of gas analyzers) for its determination are required. In the paper system for gas composition measurement at inlet and outlet of e-b installation are described. Process parameters are continuously monitoring by CEM system and occasionally by the grab sample system. Both system have been tested at pilot plant at EPS Kawȩczyn.

  15. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Continued to solicit industry research partners to provide test sites, including Patina Oil and Gas and EOG Resources, each of whom have previously worked with ARI on a similar projects funded by the Gas Technology Institute. Both

  16. Operational experience of the industrial plant for electron beam flue gas treatment

    NASA Astrophysics Data System (ADS)

    Chmielewski, Andrzej G.; Licki, Janusz; Pawelec, Andrzej; Tymiński, Bogdan; Zimek, Zbigniew

    2004-09-01

    Electron beam flue gas treatment technology is one of the most advanced technologies among new generation processes for air pollution control. The process, which has been developed in Japan, the United States, Germany and Poland allows simultaneous removal of SO 2 and NO x with high efficiency and by-product generated can be applied as fertilizer. Two industrial installations using this technology have been constructed in the world, one in China and the second in Poland. Other plants are constructed in Japan and China. Chinese installation is mostly SO 2 removal oriented (since the NO x emission limits in China are not imposed up to now), so Polish plant one is as a matter of fact the first installation for simultaneous desulfurization and denitrification of flue gases. The plant located in EPS Pomorzany in Szczecin treats the flue gases emitted from two Benson boilers of 65 MW e and 100 MW th each. The flue gases of maximum flow of 270 000 N m 3/h are irradiated by four accelerators of 700 keV electron energy and 260 kW beam power each. Description of the plant and the results obtained have been presented in this paper. The plant has been in operation for more than 2500 h (5500 h including one accelerator set operation). Removal efficiencies up to 95% for SO 2 and up to 70% for NO x were achieved. Several thousand tons of the by-product was sold in the form of NPK fertilizer. Economically, the technology is competitive with the conventional ones.

  17. TREATMENT OF PRODUCED OIL AND GAS WATERS WITH SURFACTANT-MODIFIED ZEOLITE

    SciTech Connect

    Lynn E. Katz; E.J. Sullivan; R.S. Bowman

    2000-10-31

    Whereas most water produced from onshore oil and gas operations is disposed via reinjection, some waters, such as those from offshore production platforms, coastal production, and some onshore wells, must be treated to remove organic constituents before the water is discharged. Current methods for reducing residual free phases and dissolved organic carbon are not always fully effective in meeting regulatory limits. In addition, cost, space requirements, and ease of use are important factors in any treatment system. Surfactant-modified zeolite (SMZ) has been used successfully to treat contaminated ground water for organic and inorganic constituents. This research will use laboratory batch and column studies to design a field system that will be used to treat produced waters to reduce dissolved and free-phase organic constituents. The system will be designed to operate simply and to have low operating costs. Methods for regeneration of the spent zeolite will also be tested, as will the treatment system at a field production site in the final project task. Research over the past six months has focused on the method development, batch adsorption studies to demonstrate removal of target organic constituents, and the selection of a likely test site and characterization of produced waters from the site. Current contacts for selection, and ultimately, testing of example oil field waters include Phillips Petroleum Corp. (offshore location, Gulf of Mexico); MCA Petroleum Corporation in Flatonia, Texas; Amoco production in Farmington, New Mexico; and the New Mexico Bureau of Mines and Mineral Resources (mining operators for coal bed waters from the Farmington area). Water from Phillips Petroleum was received in August and analyzed at the University of Texas. These waters are being used in the laboratory to evaluate interactions between oil field waters and the SMZ. A site visit to MCA Petroleum operations was undertaken on October 12, 2000, and the analyses of samples taken

  18. A study for the thermal treatment of dehydrated sewage sludge with gas-agitated double screw type dryer.

    PubMed

    Kim, Hey-Suk; Shin, Mi-Soo; Jang, Dong-Soon; Na, Eun-Soo

    2005-01-01

    A specially designed dryer has been developed for the thermal treatment of dehydrated, highly viscous sewage sludge with moisture content more than 80 wt.% by an gas-agitated, double-screw type dryer system. The treatment capacity of sludge dryer was about 100 kg/h. It consists of burner, feeding hopper, hot gas supplying ducts with double screw conveyor, damper and outlets of drying gas and dried material. The sewage sludge was transported by the revolution of the cylinder conveyor together with the tumbling and mixing action of the screw and lifters. The heating of the sludge was made efficient by the combination action of conduction and convection modes together with the gas-agitation process. The conduction occurred across the surface of the combustor cylinder, the convection was made by the flue gas interaction over the sludge and the agitation action through holes of conveyor cylinder into the bottom of the sludge. The number and location of gas-agitation holes and thereby the fraction of drying gas into the agitation holes were evaluated by numerical calculation of turbulent reacting flow. To evaluate the performance of the dryer developed in this study, a series of parametric experiments were performed in terms of important variables. In general drying process occurred successfully even for the highly agglomerating municipal sewage sludge through the first lumped plastic phase to a fine granulate state when the heat and mass balance was matched by adjusting rpm of the conveyor, burner capacity, and the fraction of gas-agitation. Further the avoidance of initial sludge agglomeration was considered to be important by the combination action of screw and lifter. The weight of the sludge was reduced approximately by 60% and therefore the volume of sludge was decreased to approximately 75% of initial volume with the water content of 10-20%. Energy efficiency of dryer was evaluated in the range of 70-75% at the sludge feed rate, 100 kg/h. The results obtained show

  19. Treatment of gas industry wastes using the biological granular activated carbon fluidized bed reactor process. Annual report, August 1994

    SciTech Connect

    Hickey, R.; Wagner, D.; Sunday, A.; Heine, B.; Rajan, R.

    1994-08-01

    The Granular Activated Carbon-Fluidized Bed Reactor (GAC-FBR) system is a high rate process that combines the advantages of biological and physical-chemical treatment in a single unit operation. The process is particularly well-suited to treatment of contaminants present in water and wastewater at relatively low concentrations. Process economics indicate the GAC-FBR can be extremely cost-effective compared to aqueous phase GAC adsorption and air stripping followed by vapor phase control. Accordingly, three field trials are scheduled for the next 18 months; one at a manufactured gas plant site (PAHs), one at a gas dehydration site (BTEX), and one to treat a chlorinated solvent (TCE) at a government installation.

  20. Gas Generation and Hold-Up in Hanford Waste Treatment Plant Process Streams Containing Anti-Foam Agent (AFA)

    SciTech Connect

    Arm, Stuart T.; Poloski, Adam P.; Stewart, Charles W.; Meyer, Perry A.; Kurath, Dean E.

    2007-06-29

    The Waste Treatment and Immobilization Plant (WTP) is being designed and built to pretreat and vitrify defense wastes stored at the DOE Hanford Site near Richland, Washington. Some of the WTP process streams are slurries that exhibit non-Newtonian rheological behavior. Such streams can accumulate hazardous quantities of thermally and radiolytically generated flammable gases. Experiments were performed in a bubble column to measure gas hold-up under various conditions to better understand flammable gas behavior in WTP processes. The two non-Newtonian slurries tested were kaolin-bentonite clay and a chemical surrogate of pretreated high-level waste (HLW) from Hanford Tank AZ-101. The addition of solutes, whether a salt or anti-foaming agent (AFA) decrease the bubble coalescence rate leading to smaller bubbles, lower bubble rise velocity and higher gas holdup. Gas holdup decreased with increasing yield stress and consistency. The impact of AFA on gas holdup in kaolin-bentonite clay was less than in simulated HLW, presumably because the AFA adsorbed onto the clay particles, rendering it unavailable to retard coalescence.

  1. Impact of surface structure and feed gas composition on Bacillus subtilis endospore inactivation during direct plasma treatment

    PubMed Central

    Hertwig, Christian; Steins, Veronika; Reineke, Kai; Rademacher, Antje; Klocke, Michael; Rauh, Cornelia; Schlüter, Oliver

    2015-01-01

    This study investigated the inactivation efficiency of cold atmospheric pressure plasma treatment on Bacillus subtilis endospores dependent on the used feed gas composition and on the surface, the endospores were attached on. Glass petri-dishes, glass beads, and peppercorns were inoculated with the same endospore density and treated with a radio frequency plasma jet. Generated reactive species were detected using optical emission spectroscopy. A quantitative polymerase chain reaction (qPCR) based ratio detection system was established to monitor the DNA damage during the plasma treatment. Argon + 0.135% vol. oxygen + 0.2% vol. nitrogen as feed gas emitted the highest amounts of UV-C photons and considerable amount of reactive oxygen and nitrogen species. Plasma generated with argon + 0.135% vol. oxygen was characterized by the highest emission of reactive oxygen species (ROS), whereas the UV-C emission was negligible. The use of pure argon showed a negligible emission of UV photons and atomic oxygen, however, the emission of vacuum (V)UV photons was assumed. Similar maximum inactivation results were achieved for the three feed gas compositions. The surface structure had a significant impact on the inactivation efficiency of the plasma treatment. The maximum inactivation achieved was between 2.4 and 2.8 log10 on glass petri-dishes and 3.9 to 4.6 log10 on glass beads. The treatment of peppercorns resulted in an inactivation lower than 1.0 log10. qPCR results showed a significant DNA damage for all gas compositions. Pure argon showed the highest results for the DNA damage ratio values, followed by argon + 0.135% vol. oxygen + 0.2% vol. nitrogen. In case of argon + 0.135% vol. oxygen the inactivation seems to be dominated by the action of ROS. These findings indicate the significant role of VUV and UV photons in the inactivation process of B. subtilis endospores. PMID:26300855

  2. Impact of surface structure and feed gas composition on Bacillus subtilis endospore inactivation during direct plasma treatment.

    PubMed

    Hertwig, Christian; Steins, Veronika; Reineke, Kai; Rademacher, Antje; Klocke, Michael; Rauh, Cornelia; Schlüter, Oliver

    2015-01-01

    This study investigated the inactivation efficiency of cold atmospheric pressure plasma treatment on Bacillus subtilis endospores dependent on the used feed gas composition and on the surface, the endospores were attached on. Glass petri-dishes, glass beads, and peppercorns were inoculated with the same endospore density and treated with a radio frequency plasma jet. Generated reactive species were detected using optical emission spectroscopy. A quantitative polymerase chain reaction (qPCR) based ratio detection system was established to monitor the DNA damage during the plasma treatment. Argon + 0.135% vol. oxygen + 0.2% vol. nitrogen as feed gas emitted the highest amounts of UV-C photons and considerable amount of reactive oxygen and nitrogen species. Plasma generated with argon + 0.135% vol. oxygen was characterized by the highest emission of reactive oxygen species (ROS), whereas the UV-C emission was negligible. The use of pure argon showed a negligible emission of UV photons and atomic oxygen, however, the emission of vacuum (V)UV photons was assumed. Similar maximum inactivation results were achieved for the three feed gas compositions. The surface structure had a significant impact on the inactivation efficiency of the plasma treatment. The maximum inactivation achieved was between 2.4 and 2.8 log10 on glass petri-dishes and 3.9 to 4.6 log10 on glass beads. The treatment of peppercorns resulted in an inactivation lower than 1.0 log10. qPCR results showed a significant DNA damage for all gas compositions. Pure argon showed the highest results for the DNA damage ratio values, followed by argon + 0.135% vol. oxygen + 0.2% vol. nitrogen. In case of argon + 0.135% vol. oxygen the inactivation seems to be dominated by the action of ROS. These findings indicate the significant role of VUV and UV photons in the inactivation process of B. subtilis endospores. PMID:26300855

  3. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) The search for another field site was abandoned after discussion with DOE. There is a clear absence of willing industry partners to participate in this project. The greatest obstacle is having the necessary data to perform the

  4. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Finished preparing the final project report, less the field implementation component. Sent to DOE for review. (2) Continued coordinating the final selection of candidates and field implementation with Oneok. Oneok postponed field

  5. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Type curve matching continued during the reporting period. (2) A second data collection trip to Tulsa was performed to gather information on the additional reservoirs to be included in the analysis. Created updated database

  6. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Completed both type curve and artificial neural network analysis of the field. Developed list of production enhancement candidates. (2) Made final presentation of results to Oneok in Tulsa (February 26). (3) Made presentations on

  7. Wetland treatment of oil and gas well wastewaters. Quarterly technical report, May 25, 1992---August 24, 1992

    SciTech Connect

    Kadlec, R.H.; Srinivasan, K.R.

    1995-11-01

    The purpose of this study is to extend the knowledge base for wetland treatment to include processes and substances of particular importance to small, on-site systems receiving oil and gas well waste water. Collection of data on the sorption of heavy metals and the degradation of toxic organics is one of the key tasks. The toxic organics phenolics and anthracene, and chromium and copper have been selected as target adsorbates. An information search was performed on oil refinery waste treatment wetland systems.

  8. TREATMENT TANK OFF-GAS TESTING FOR THE ENHANCED CHEMICAL CLEANING PROCESS

    SciTech Connect

    Wiersma, B.

    2011-08-29

    The purpose of this activity was to provide a bounding estimate of the volume of hydrogen gas generated during Enhanced Chemical Cleaning (ECC) of residual sludge remaining in a Type I or Type II treatment tank as well as to provide results independent of the sludge volume in the waste tank to be cleaned. Previous testing to support Chemical Cleaning was based on a 20:1 oxalic acid to sludge ratio. Hydrogen gas evolution is the primary safety concern. Sealed vessel coupon tests were performed to estimate the hydrogen generation rate due to corrosion of carbon steel by 2.5 wt.% oxalic acid. These tests determined the maximum instantaneous hydrogen generation rate, the rate at which the generation rate decays, and the total hydrogen generated. These values were quantified based on a small scale methodology similar to the one described in WSRC-STI-2007-00209, Rev. 0. The measured rates support identified Safety Class functions. The tests were performed with ASTM A285 Grade C carbon steel coupons. Bounding conditions were determined for the solution environment. The oxalic acid concentration was 2.5 wt.% and the test temperature was 75 C. The test solution was agitated and contained no sludge simulant. Duplicate tests were performed and showed excellent reproducibility for the hydrogen generation rate and total hydrogen generated. The results showed that the hydrogen generation rate was initially high, but decayed rapidly within a couple of days. A statistical model was developed to predict the instantaneous hydrogen generation rate as a function of exposure time by combining both sets of data. An upper bound on the maximum hydrogen generation rate was determined from the upper 95% confidence limit. The upper bound confidence limit for the hydrogen generation rate is represented by the following equation. ln (G{sub v}) = -8.22-0.0584 t + 0.0002 t{sup 2}. This equation should be utilized to estimate the instantaneous hydrogen generation rate per unit surface area, G

  9. Influence of mechanical-biological waste pre-treatment methods on the gas formation in landfills

    SciTech Connect

    Bockreis, A. . E-mail: a.bockreis@iwar.tu-darmstadt.de; Steinberg, I.

    2005-07-01

    In order to minimise emissions and environmental impacts, only pre-treated waste should be disposed of. For the last six years, a series of continuous experiments has been conducted at the Institute WAR, TU Darmstadt, in order to determine the emissions from pre-treated waste. Different kinds of pre-treated waste were incubated in several reactors and various data, including production and composition of the gas and the leachate, were collected. In this paper, the interim results of gas production and the gas composition from different types of waste after a running time of six years are presented and discussed.

  10. Gas injection to inhibit migration during an in situ heat treatment process

    DOEpatents

    Kuhlman, Myron Ira; Vinegar; Harold J.; Baker, Ralph Sterman; Heron, Goren

    2010-11-30

    Methods of treating a subsurface formation are described herein. Methods for treating a subsurface treatment area in a formation may include introducing a fluid into the formation from a plurality of wells offset from a treatment area of an in situ heat treatment process to inhibit outward migration of formation fluid from the in situ heat treatment process.

  11. Method for generating a highly reactive plasma for exhaust gas after treatment and enhanced catalyst reactivity

    SciTech Connect

    Whealton, John H.; Hanson, Gregory R.; Storey, John M.; Raridon, Richard J.; Armfield, Jeffrey S.; Bigelow, Timothy S.; Graves, Ronald L.

    2000-07-01

    This patent application describes a method and apparatus of exhaust gas remediation that enhance the reactivity of the material catalysts found within catalytic converters of cars, trucks, and power stations.

  12. Comparison of different modeling approaches to better evaluate greenhouse gas emissions from whole wastewater treatment plants.

    PubMed

    Corominas, Lluís; Flores-Alsina, Xavier; Snip, Laura; Vanrolleghem, Peter A

    2012-11-01

    New tools are being developed to estimate greenhouse gas (GHG) emissions from wastewater treatment plants (WWTPs). There is a trend to move from empirical factors to simple comprehensive and more complex process-based models. Thus, the main objective of this study is to demonstrate the importance of using process-based dynamic models to better evaluate GHG emissions. This is tackled by defining a virtual case study based on the whole plant Benchmark Simulation Model Platform No. 2 (BSM2) and estimating GHG emissions using two approaches: (1) a combination of simple comprehensive models based on empirical assumptions and (2) a more sophisticated approach, which describes the mechanistic production of nitrous oxide (N(2) O) in the biological reactor (ASMN) and the generation of carbon dioxide (CO(2) ) and methane (CH(4) ) from the Anaerobic Digestion Model 1 (ADM1). Models already presented in literature are used, but modifications compared to the previously published ASMN model have been made. Also model interfaces between the ASMN and the ADM1 models have been developed. The results show that the use of the different approaches leads to significant differences in the N(2) O emissions (a factor of 3) but not in the CH(4) emissions (about 4%). Estimations of GHG emissions are also compared for steady-state and dynamic simulations. Averaged values for GHG emissions obtained with steady-state and dynamic simulations are rather similar. However, when looking at the dynamics of N(2) O emissions, large variability (3-6 ton CO(2) e day(-1) ) is observed due to changes in the influent wastewater C/N ratio and temperature which would not be captured by a steady-state analysis (4.4 ton CO(2) e day(-1) ). Finally, this study also shows the effect of changing the anaerobic digestion volume on the total GHG emissions. Decreasing the anaerobic digester volume resulted in a slight reduction in CH(4) emissions (about 5%), but significantly decreased N(2) O emissions in

  13. Perspectives on greenhouse gas emission estimates based on Australian wastewater treatment plant operating data.

    PubMed

    de Haas, D W; Pepperell, C; Foley, J

    2014-01-01

    Primary operating data were collected from forty-six wastewater treatment plants (WWTPs) located across three states within Australia. The size range of plants was indicatively from 500 to 900,000 person equivalents. Direct and indirect greenhouse gas emissions were calculated using a mass balance approach and default emission factors, based on Australia's National Greenhouse Energy Reporting (NGER) scheme and IPCC guidelines. A Monte Carlo-type combined uncertainty analysis was applied to the some of the key emission factors in order to study sensitivity. The results suggest that Scope 2 (indirect emissions due to electrical power purchased from the grid) dominate the emissions profile for most of the plants (indicatively half to three quarters of the average estimated total emissions). This is only offset for the relatively small number of plants (in this study) that have significant on-site power generation from biogas, or where the water utility purchases grid electricity generated from renewable sources. For plants with anaerobic digestion, inventory data issues around theoretical biogas generation, capture and measurement were sometimes encountered that can skew reportable emissions using the NGER methodology. Typically, nitrous oxide (N(2)O) emissions dominated the Scope 1 (direct) emissions. However, N(2)O still only accounted for approximately 10 to 37% of total emissions. This conservative estimate is based on the 'default' NGER steady-state emission factor, which amounts to 1% of nitrogen removed through biological nitrification-denitrification processing in the plant (or indicatively 0.7 to 0.8% of plant influent total nitrogen). Current research suggests that true N(2)O emissions may be much lower and certainly not steady-state. The results of this study help to place in context research work that is focused on direct emissions from WWTPs (including N(2)O, methane and carbon dioxide of non-biogenic origin). For example, whereas non-biogenic CO(2

  14. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Continued to solicit industry research partners to provide test sites. A Cooperative Research Agreement has been signed with Oneok, for a test site in the Mocane-Laverne field in the Anadarko basin (Oklahoma). The site consists of

  15. Methodology for development of treatment and disposal options for compressed gas cylinders contaminated with radionuclides

    SciTech Connect

    Conley, T.B.; Czor, K.R.; Wright, W.T.

    1996-06-01

    Compressed gas cylinders contaminated with radionuclides are a unique waste item that may become a Resource Conservation and Recovery Act (RCRA) hazardous waste through two mechanisms: either the contents of the compressed gas cylinder are regulated under RCRA or the internal pressure of the compressed gas cylinder gives it the characteristic of reactivity. The characteristic of reactivity is defined by RCRA in 40 Code of Federal Regulations (CFR) 261.23(a)(6) as a waste that is capable of detonation or explosive reaction if it is subjected to a strong initiating source or heated under confinement. In a letter dated September 1, 1989, the U.S. Environmental Protection Agency (EPA) Office of Solid Waste referred the interpretation of the definition of reactivity to the EPA Regional Office and/or the state (if the state has primacy). The Tennessee Department of Environment and Conservation (TDEC) has made the interpretation that to meet the definition of reactive as specified in 40 CFR 261.23(a)(6) there must be a chemical reaction that causes the explosion or detonation. This interpretation limits the compressed gas cylinders that have to be treated as RCRA hazardous waste to those that have other RCRA characteristic codes or contain listed wastes. The difficulty in treating compressed gas cylinders is heightened in the case of radiologically contaminated compressed gas cylinders because the internal pressure and possible hazardous constituents must be treated in most cases before decontamination of the cylinder is possible. Special procedures must be followed to ensure that radiological contamination is not transferred to clean gas cylinders or released into the environment.

  16. Flue gas treatment for SO2 removal with air-sparged hydrocyclone technology.

    PubMed

    Bokotko, Romuald P; Hupka, Jan; Miller, Jan D

    2005-02-15

    Laboratory results from an initial study on the removal of SO2 from gas mixtures are reported using air-sparged hydrocyclone (ASH) technology. Tap water and alkaline solutions were used for absorption, and the influence of gas flow rate, water flow rate, and length of the ASH unit were investigated. The research results indicate thatthe air-sparged hydrocyclone can be used as a highly efficient absorber for SO2 emissions. The ASH allows for 97% SO2 removal using water alone for sulfur dioxide content in the gas phase of 5 g/m3. All SO2 is removed in weakly alkaline solution (0.01 mol NaOH/dm3).

  17. Effectiveness of superheated steam and gas catalytic infrared heat treatments to inactivate Salmonella on raw almonds.

    PubMed

    Bari, Latiful; Nei, Daisuke; Sotome, Itaru; Nishina, Ikuo Y; Hayakawa, Fumiyo; Isobe, Seiichi; Kawamoto, Shinnichi

    2010-07-01

    The majority of the almond-related outbreaks have been associated with Salmonella. Therefore, it is necessary to find an effective method to inactivate these organisms on the raw almond before distribution in the market. This study was conducted to assess the effectiveness of superheated steam (SHS) treatments followed by catalytic infrared (IR) heat treatment to inactivate Salmonella populations on raw almond and to determine the effect of these treatments on the quality of raw almond. It has been found that SHS treatment for 70 seconds followed by catalytic IR heat treatment for 70 seconds was able to reduce 5.73 +/- 0.11 log CFU/g Salmonella population, and no survivors were found in the enrichment medium. The overall visual quality parameters of both treated and nontreated almonds were found within the acceptable limit. Therefore, SHS treatments for 70 seconds followed by catalytic IR heat treatment for 70 seconds could be an effective decontamination method for raw almonds.

  18. Hot waste-to-energy flue gas treatment using an integrated fluidised bed reactor.

    PubMed

    Bianchini, A; Pellegrini, M; Saccani, C

    2009-04-01

    This paper describes an innovative process to increase superheated steam temperatures in waste-to-energy (WTE) plants. This solution is mainly characterised by a fluidised bed reactor in which hot flue gas is treated both chemically and mechanically. This approach, together with gas recirculation, increases the energy conversion efficiency, and raises the superheated steam temperature without decreasing the useful life of the superheater. This paper presents new experimental data obtained from the test facility installed at the Hera S.p.A. WTE plant in Forlì, Italy; discusses changes that can be implemented to increase the duration of experimental testing; offers suggestions for the design of an industrial solution.

  19. A UNIFIED MONTE CARLO TREATMENT OF GAS-GRAIN CHEMISTRY FOR LARGE REACTION NETWORKS. II. A MULTIPHASE GAS-SURFACE-LAYERED BULK MODEL

    SciTech Connect

    Vasyunin, A. I.; Herbst, Eric E-mail: eh2ef@virginia.edu

    2013-01-10

    The observed gas-phase molecular inventory of hot cores is believed to be significantly impacted by the products of chemistry in interstellar ices. In this study, we report the construction of a full macroscopic Monte Carlo model of both the gas-phase chemistry and the chemistry occurring in the icy mantles of interstellar grains. Our model treats icy grain mantles in a layer-by-layer manner, which incorporates laboratory data on ice desorption correctly. The ice treatment includes a distinction between a reactive ice surface and an inert bulk. The treatment also distinguishes between zeroth- and first-order desorption, and includes the entrapment of volatile species in more refractory ice mantles. We apply the model to the investigation of the chemistry in hot cores, in which a thick ice mantle built up during the previous cold phase of protostellar evolution undergoes surface reactions and is eventually evaporated. For the first time, the impact of a detailed multilayer approach to grain mantle formation on the warm-up chemistry is explored. The use of a multilayer ice structure has a mixed impact on the abundances of organic species formed during the warm-up phase. For example, the abundance of gaseous HCOOCH{sub 3} is lower in the multilayer model than in previous grain models that do not distinguish between layers (so-called two phase models). Other gaseous organic species formed in the warm-up phase are affected slightly. Finally, we find that the entrapment of volatile species in water ice can explain the two-jump behavior of H{sub 2}CO previously found in observations of protostars.

  20. Laboratory and field evaluation of the gas treatment approach for insitu remediation of chromate-contaminated soils

    SciTech Connect

    Thornton, E.C.; Jackson, R.L.

    1994-04-01

    Laboratory scale soil treatment tests have been conducted as part of an effort to develop and implement an in situ chemical treatment approach to the remediation of chromate-contaminated soils through the use of reactive gases. These tests involved three different soil samples that were contaminated with Cr(VI) at the 200 ppM level. Treatment of the contaminated soils was performed by passing 100 ppM and 2000 ppM concentrations of hydrogen sulfide in nitrogen through soil columns until a S:Cr mole ratio of 10:1 was achieved. The treated soils were then leached with groundwater or deionized water and analyzed to assess the extent of chromium immobilization. Test results indicate >90% immobilization of chromium and demonstrate that the treatment process is irreversible. Ongoing developmental efforts are being directed towards the demonstration and evaluation of the gas treatment approach in a field test at a chromate-contaminated site. Major planned activities associated with this demonstration include laboratory testing of waste site soil samples, design of the treatment system and injection/extraction well network, geotechnical and geochemical characterization of the test site, and identification and resolution of regulatory and safety requirements.

  1. Biological treatment of waste gas containing mixture of monochlorobenzene (MCB) and benzene in a bench scale biofilter.

    PubMed

    Pandey, R A; Joshi, P R; Mudliar, S N; Deshmukh, S C

    2010-07-01

    The paper outlines treatment of waste gas containing monochlorobenzene (MCB) and benzene in a mixture using biofilter packed with compost and woodchips seeded with Acinetobacter calcoaceticus. The biofilter could treat waste gas containing MCB and benzene effectively with an efficiency of (99+/-5%) and (97+/-6%) at optimal empty bed contact time (EBCT) of 3 min with a loading of 57 g/m(3)/h of MCB and 2g/m(3)/h of benzene. At optimum loading of MCB and benzene, the biofilter showed total bacterial count of 13 x 10(5)CFU/g of compost, while the MCB and benzene degrading bacterial count was 71 x 10(4)CFU/g and 5 x 10(4)CFU/g compost respectively. The experimental removal efficiency of MCB and benzene were in good agreement with the model predicted value. PMID:20202831

  2. Comparing feed-forward versus neural gas as estimators: application to coke wastewater treatment.

    PubMed

    Machón-González, Iván; López-García, Hilario; Rodríguez-Iglesias, Jesús; Marañón-Maison, Elena; Castrillón-Peláez, Leonor; Fernández-Nava, Yolanda

    2013-01-01

    Numerous papers related to the estimation of wastewater parameters have used artificial neural networks. Although successful results have been reported, different problems have arisen such as overtraining, local minima and model instability. In this paper, two types of neural networks, feed-forward and neural gas, are trained to obtain a model that estimates the values of nitrates in the effluent stream of a three-step activated sludge system (two oxic and one anoxic). Placing the denitrification (anoxic) step at the head of the process can force denitrifying bacteria to use internal organic carbon. However, methanol has to be added to achieve high denitrification efficiencies in some industrial wastewaters. The aim of this paper is to compare the two networks in addition to suggesting a methodology to validate the models. The influence of the neighbourhood radius is important in the neural gas approach and must be selected correctly. Neural gas performs well due to its cooperation--competition procedure, with no problems of stability or overfitting arising in the experimental results. The neural gas model is also interesting for use as a direct plant model because of its robustness and deterministic behaviour.

  3. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

    SciTech Connect

    Scott Reeves

    2003-03-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Prepared various materials to describe the project for promotional purposes and to attract potential industry partners. Materials included slides for DOE's displays at the SPE Eastern Regional and Annual Technical Conference, and

  4. SLUDGE TREATMENT PROJECT KOP DISPOSITION - THERMAL AND GAS ANALYSIS FOR THE COLD VACUUM DRYING FACILITY

    SciTech Connect

    SWENSON JA; CROWE RD; APTHORPE R; PLYS MG

    2010-03-09

    will expand the calculations presented in this document to include: additional features of the drying cycle, more realistic treatment of uranium metal consumption during oxidation, larger water inventory, longer time scales, and graphing of results of hydrogen gas concentration.

  5. Wetland treatment of oil and gas well wastewaters. Quarterly technical report, March 25, 1994--May 24, 1994

    SciTech Connect

    Kadlec, R.H.; Srinivasan, K.R.

    1994-06-22

    In the present report, the simultaneous uptake of Cu(II) and Cr(VI) by laboratory-type wetlands has been considered. Two different molar ratios (Cu(II)/Cr(VI)) of 3.8 and 0.46 have been used. Because most oil and gas waste waters are known to contain both cationic and anionic heavy metals in the dissolved form, a study of simultaneous uptake of cationic and anionic heavy metals will be helpful in the design and construction of a wetland treatment system, for such waste waters.

  6. Quantification of greenhouse gas (GHG) emissions from wastewater treatment plants using a ground-based remote sensing approach

    NASA Astrophysics Data System (ADS)

    Delre, Antonio; Mønster, Jacob; Scheutz, Charlotte

    2016-04-01

    The direct release of nitrous oxide (N2O) and methane (CH4) from wastewater treatment plants (WWTP) is important because it contributes to the global greenhouse gases (GHGs) release and strongly effects the WWTP carbon footprint. Biological nitrogen removal technologies could increase the direct emission of N2O (IPCC, 2006), while CH4 losses are of environmental, economic and safety concern. Currently, reporting of N2O and CH4 emissions from WWTPs are performed mainly using methods suggested by IPCC which are not site specific (IPCC, 2006). The dynamic tracer dispersion method (TDM), a ground based remote sensing approach implemented at DTU Environment, was demonstrated to be a novel and successful tool for full-scale CH4 and N2O quantification from WWTPs. The method combines a controlled release of tracer gas from the facility with concentration measurements downwind of the plant (Mønster et al., 2014; Yoshida et al., 2014). TDM in general is based on the assumption that a tracer gas released at an emission source, in this case a WWTP, disperses into the atmosphere in the same way as the GHG emitted from process units. Since the ratio of their concentrations remains constant along their atmospheric dispersion, the GHG emission rate can be calculated using the following expression when the tracer gas release rate is known: EGHG=Qtr*(CGHG/Ctr)*(MWGHG/MWtr) EGHG is the GHG emission in mass per time, Qtr is the tracer release in mass per time, CGHG and Ctr are the concentrations measured downwind in parts per billion subtracted of their background values and integrated over the whole plume, and MWGHG and MWtr are the molar weights of GHG and tracer gas respectively (Mønster et al. 2014). In this study, acetylene (C2H2) was used as tracer. Downwind plume concentrations were measured driving along transects with two cavity ring down spectrometers (Yoshida et al., 2014). TDM was successfully applied in different seasons at several Scandinavian WWTPs characterized by

  7. Treatment of Nematodes with Ozone Gas: A Sustainable Alternative to Nematicides

    NASA Astrophysics Data System (ADS)

    Msayleb, Nahed; Ibrahim, Saiid

    This study tests Ozone as a Nematicides' alternative. Nematode-infected soil samples were treated with ascending doses of O3 by submerging the outlet of an "MB1000 Ozone Generator" in the 40 ml samples; then to test the O3 nematicidal effect by gas fumigation, Ozone gas was released into a sealed bag containing 80 g of each of the 6 nematode-infected soil samples with ascending doses and a repetition of each. With water-ozonation, 900 mg O3 were needed to kill 100% of nematodes, and the O3-Nematodes LD50 was identified by 420 mg. With the second experiment, O3 soil fumigation for 50 minutes at a dose of 1,125 mg in an air volume of 5 litres, were needed to control 95% of living nematodes.

  8. [Treatment of Flue Gas from Sludge Drying Process by A Thermophilic Biofilter].

    PubMed

    Chen, Wen-he; Deng, Ming-jia; Luo, Hui; Ding, Wen-iie; Li, Lin; Lin, Jian; Liu, Jun-xin

    2016-01-15

    A thermophilic biofilter was employed to treat the flue gas generated from sludge drying process, and the performance in both the start period and the stationary phase was studied under the gas flow rate of 2 700-3 100 m3 x h(-1) and retention time of 21.88-25.10 s. The results showed that the thermophilic biofilter could effectively treat gases containing sulfur dioxide, ammonia and volatile organic compounds (VOC). The removal efficiencies could reach 100%, 93.61% and 87.01%, respectively. Microbial analysis indicated that most of the population belonged to thermophilic bacteria. Paenibacillus sp., Chelatococcus sp., Bacillus sp., Clostridium thermosuccinogenes, Pseudoxanthomonas sp. and Geobacillus debilis which were abundant in the thermophilic biofilter, had the abilities of denitrification, desulfurization and degradation of volatile organic compounds.

  9. Flue gas desulfurization and by-product treatment at Tisov power plant (Czech Republic)

    SciTech Connect

    Valbert, G.; Schneider, G.

    1998-07-01

    The FGD plant Tisovain the Czech republic is a retrofit downstream of a 100 MW lignite fired power plant. It was designed and built by L. and C. STEINMUELLER GmbH. Despite a narrow time schedule, the project was finished on time in December 1997. The major objectives of the applied limestone/gypsum process are: Minimum investment and operating costs; production and environmentally neutral disposal of a stabilized product containing the by-products fly ash, slag, gypsum and effluent. The first objective is achieved by the following new process arrangement: The flue gas is taken over from the boiler and fed directly into a wet scrubber for absorptive removal of the acid gases SO{sub 2}, HCl and HF. The cleaned flue gas is vented into the atmosphere without reheating by means of a wet stack which is arranged on top of the scrubber. By the described arrangement, a heat exchanger for cooling/heating of the flue gas is not required. No ductwork for connecting scrubber and stack is needed. Furthermore, the pressure drop across the FGD plant is minimized and allows the use of the already existing flue gas fans. Based on Steinmueller's experience with various limestone qualities, the powdered limestone supplied to the plant is milled once more on site. Thereby the reactivity of the limestone is enhanced resulting in low power consumption for the required plant performance. The second objective is achieved as follows: A part of the scrubbing liquid is continuously bled off as the underflow of a hydrocyclone station in order to remove the gypsum produced in the scrubber. A further dewatering of the gypsum does not take place. Instead, the effluent is mixed with fly ash and slag. As an additive, lime slaked with slag slurry is added. The resulting mixture is disposed of and compacted in the nearby opencast mine workings. It hardens in cement-like setting reactions to an environmentally safe stabilized product.

  10. The treatment of capital in estimating fair market value of oil and gas properties

    SciTech Connect

    Hartsock, J.H.; Gruy, H.J.

    1995-12-31

    Fair market value has its origin in law and is defined as that price that a willing buyer will pay and a willing seller will sell at some point in time, with neither the buyer nor the seller under any compulsion to buy or sell, aid both having equal and reasonable knowledge of the facts. In reality, a perfect sale probably never occurs in which a willing buyer and a willing seller are under no compulsion to buy or sell and both are equally familiar with all the facts. Nonetheless, it is necessary to prepare fair market value estimates for oil and gas properties for the purpose of gift taxes, estate taxes, condemnation cases, mergers and divorce settlements. For the estimation of the fair market value of oil and gas properties, there are basically two approaches; namely, the income approach and the market data approach. The income approach requires the estimation of reserves, identification of their categories (proved, probable and possible), a detailed cash flow projection and the proper application of risk factors. The market data approach utilizes the comparable sales of properties The comparable sales approach is preferred, but for producing oil and gas properties it is difficult to identify sales comparable in net reserves, product prices, location, operating expenses, operator expertise, etc. Consequently, for proved, probable and possible reserves, the income approach has been accepted by the courts and is more generally applied. For nonproducing mineral interests the comparable sales approach is applied using multiples of lease bonuses in the area.

  11. Formation of the ZnFe2O4 phase in an electric arc furnace off-gas treatment system.

    PubMed

    Suetens, T; Guo, M; Van Acker, K; Blanpain, B

    2015-04-28

    To better understand the phenomena of ZnFe2O4 spinel formation in electric arc furnace dust, the dust was characterized with particle size analysis, X-ray fluorescence (XRF), electron backscatter diffraction (EBSD), and electron probe micro-analysis (EPMA). Different ZnFe2O4 formation reaction extents were observed for iron oxide particles with different particle sizes. ZnO particles were present as both individual particles and aggregated on the surface of larger particles. Also, the slag particles found in the off-gas were shown not to react with the zinc vapor. After confirming the presence of a ZnFe2O4 formation reaction, the thermodynamic feasibility of in-process separation - a new electric arc furnace dust treatment technology - was reevaluated. The large air intake and the presence of iron oxide particles in the off-gas were included into the thermodynamic calculations. The formation of the stable ZnFe2O4 spinel phase was shown to be thermodynamically favorable in current electric arc furnace off-gas ducts conditions even before reaching the post combustion chamber.

  12. Hydrogen gas treatment prolongs replicative lifespan of bone marrow multipotential stromal cells in vitro while preserving differentiation and paracrine potentials

    SciTech Connect

    Kawasaki, Haruhisa; Guan, Jianjun; Tamama, Kenichi

    2010-07-02

    Cell therapy with bone marrow multipotential stromal cells/mesenchymal stem cells (MSCs) represents a promising approach in the field of regenerative medicine. Low frequency of MSCs in adult bone marrow necessitates ex vivo expansion of MSCs after harvest; however, such a manipulation causes cellular senescence with loss of differentiation, proliferative, and therapeutic potentials of MSCs. Hydrogen molecules have been shown to exert organ protective effects through selective reduction of hydroxyl radicals. As oxidative stress is one of the key insults promoting cell senescence in vivo as well as in vitro, we hypothesized that hydrogen molecules prevent senescent process during MSC expansion. Addition of 3% hydrogen gas enhanced preservation of colony forming early progenitor cells within MSC preparation and prolonged the in vitro replicative lifespan of MSCs without losing differentiation potentials and paracrine capabilities. Interestingly, 3% hydrogen gas treatment did not decrease hydroxyl radical, protein carbonyl, and 8-hydroxydeoxyguanosine, suggesting that scavenging hydroxyl radical might not be responsible for these effects of hydrogen gas in this study.

  13. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT, MOCANE-LAVERNE FIELD, OKLAHOMA

    SciTech Connect

    Scott Reeves; Buckley Walsh

    2003-08-01

    In 1996, Advanced Resources International (ARI) began performing R&D targeted at enhancing production and reserves from natural gas fields. The impetus for the effort was a series of field R&D projects in the early-to-mid 1990's, in eastern coalbed methane and gas shales plays, where well remediation and production enhancement had been successfully demonstrated. As a first step in the R&D effort, an assessment was made of the potential for restimulation to provide meaningful reserve additions to the U.S. gas resource base, and what technologies were needed to do so. That work concluded that: (1) A significant resource base did exist via restimulation (multiples of Tcf). (2) The greatest opportunities existed in non-conventional plays where completion practices were (relatively) complex and technology advancement was rapid. (3) Accurate candidate selection is the greatest single factor that contributes to a successful restimulation program. With these findings, a field-oriented program targeted at tight sand formations was initiated to develop and demonstrate successful candidate recognition technology. In that program, which concluded in 2001, nine wells were restimulated in the Green River, Piceance and East Texas basins, which in total added 2.9 Bcf of reserves at an average cost of $0.26/Mcf. In addition, it was found that in complex and heterogeneous reservoirs (such as tight sand formations), candidate selection procedures should involve a combination of fundamental engineering and advanced pattern recognition approaches, and that simple statistical methods for identifying candidate wells are not effective. In mid-2000, the U.S. Department of Energy (DOE) awarded ARI an R&D contract to determine if the methods employed in that project could also be applied to stripper gas wells. In addition, the ability of those approaches to identify more general production enhancement opportunities (beyond only restimulation), such as via artificial lift and compression, was

  14. Life cycle assessment of vertical and horizontal flow constructed wetlands for wastewater treatment considering nitrogen and carbon greenhouse gas emissions.

    PubMed

    Fuchs, Valerie J; Mihelcic, James R; Gierke, John S

    2011-02-01

    Life cycle assessment (LCA) is used to compare the environmental impacts of vertical flow constructed wetlands (VFCW) and horizontal flow constructed wetlands (HFCW). The LCAs include greenhouse gas (N(2)O, CO(2) and CH(4)) emissions. Baseline constructed wetland designs are compared to different treatment performance scenarios and to conventional wastewater treatment at the materials acquisition, assembly and operation life stages. The LCAs suggest that constructed wetlands have less environmental impact, in terms of resource consumption and greenhouse gas emissions. The VFCW is a less impactful configuration for removing total nitrogen from domestic wastewater. Both wetland designs have negligible impacts on respiratory organics, radiation and ozone. Gaseous emissions, often not included in wastewater LCAs because of lack of data or lack of agreement on impacts, have the largest impact on climate change. Nitrous oxide accounts for the increase in impact on respiratory inorganic, and the combined acidification/eutrophication category. The LCAs were used to assess the importance of nitrogen removal and recycling, and the potential for optimizing nitrogen removal in constructed wetlands.

  15. The effect of microbubbles on gas-liquid mass transfer coefficient and degradation rate of COD in wastewater treatment.

    PubMed

    Yao, Kangning; Chi, Yong; Wang, Fei; Yan, Jianhua; Ni, Mingjiang; Cen, Kefa

    2016-01-01

    A commonly used aeration device at present has the disadvantages of low mass transfer rate because the generated bubbles are several millimeters in diameter which are much bigger than microbubbles. Therefore, the effect of a microbubble on gas-liquid mass transfer and wastewater treatment process was investigated. To evaluate the effect of each bubble type, the volumetric mass transfer coefficients for microbubbles and conventional bubbles were determined. The volumetric mass transfer coefficient was 0.02905 s(-1) and 0.02191 s(-1) at a gas flow rate of 0.67 L min(-1) in tap water for microbubbles and conventional bubbles, respectively. The degradation rate of simulated municipal wastewater was also investigated, using aerobic activated sludge and ozone. Compared with the conventional bubble generator, the chemical oxygen demand (COD) removal rate was 2.04, 5.9, 3.26 times higher than those of the conventional bubble contactor at the same initial COD concentration of COD 200 mg L(-1), 400 mg L(-1), and 600 mg L(-1), while aerobic activated sludge was used. For the ozonation process, the rate of COD removal using microbubble generator was 2.38, 2.51, 2.89 times of those of the conventional bubble generator. Based on the results, the effect of initial COD concentration on the specific COD degradation rate were discussed in different systems. Thus, the results revealed that microbubbles could enhance mass transfer in wastewater treatment and be an effective method to improve the degradation of wastewater.

  16. Density functional theory screening of gas-treatment strategies for stabilization of high energy-density lithium metal anodes

    NASA Astrophysics Data System (ADS)

    Koch, Stephan L.; Morgan, Benjamin J.; Passerini, Stefano; Teobaldi, Gilberto

    2015-11-01

    To explore the potential of molecular gas treatment of freshly cut lithium foils in non-electrolyte-based passivation of high-energy-density Li anodes, density functional theory (DFT) has been used to study the decomposition of molecular gases on metallic lithium surfaces. By combining DFT geometry optimization and Molecular Dynamics, the effects of atmospheric (N2, O2, CO2) and hazardous (F2, SO2) gas decomposition on Li(bcc) (100), (110), and (111) surfaces on relative surface energies, work functions, and emerging electronic and elastic properties are investigated. The simulations suggest that exposure to different molecular gases can be used to induce and control reconstructions of the metal Li surface and substantial changes (up to over 1 eV) in the work function of the passivated system. Contrary to the other considered gases, which form metallic adlayers, SO2 treatment emerges as the most effective in creating an insulating passivation layer for dosages ≤1 mono-layer. The substantial Li → adsorbate charge transfer and adlayer relaxation produce marked elastic stiffening of the interface, with the smallest change shown by nitrogen-treated adlayers.

  17. Estimation of VOC emissions from produced-water treatment ponds in Uintah Basin oil and gas field using modeling techniques

    NASA Astrophysics Data System (ADS)

    Tran, H.; Mansfield, M. L.; Lyman, S. N.; O'Neil, T.; Jones, C. P.

    2015-12-01

    Emissions from produced-water treatment ponds are poorly characterized sources in oil and gas emission inventories that play a critical role in studying elevated winter ozone events in the Uintah Basin, Utah, U.S. Information gaps include un-quantified amounts and compositions of gases emitted from these facilities. The emitted gases are often known as volatile organic compounds (VOCs) which, beside nitrogen oxides (NOX), are major precursors for ozone formation in the near-surface layer. Field measurement campaigns using the flux-chamber technique have been performed to measure VOC emissions from a limited number of produced water ponds in the Uintah Basin of eastern Utah. Although the flux chamber provides accurate measurements at the point of sampling, it covers just a limited area of the ponds and is prone to altering environmental conditions (e.g., temperature, pressure). This fact raises the need to validate flux chamber measurements. In this study, we apply an inverse-dispersion modeling technique with evacuated canister sampling to validate the flux-chamber measurements. This modeling technique applies an initial and arbitrary emission rate to estimate pollutant concentrations at pre-defined receptors, and adjusts the emission rate until the estimated pollutant concentrations approximates measured concentrations at the receptors. The derived emission rates are then compared with flux-chamber measurements and differences are analyzed. Additionally, we investigate the applicability of the WATER9 wastewater emission model for the estimation of VOC emissions from produced-water ponds in the Uintah Basin. WATER9 estimates the emission of each gas based on properties of the gas, its concentration in the waste water, and the characteristics of the influent and treatment units. Results of VOC emission estimations using inverse-dispersion and WATER9 modeling techniques will be reported.

  18. Improvement and further development in CESM/CAM5: gas-phase chemistry and inorganic aerosol treatments

    NASA Astrophysics Data System (ADS)

    He, J.; Zhang, Y.

    2014-09-01

    Gas-phase chemistry and subsequent gas-to-particle conversion processes such as new particle formation, condensation, and thermodynamic partitioning have large impacts on air quality, climate, and public health through influencing the amounts and distributions of gaseous precursors and secondary aerosols. Their roles in global air quality and climate are examined in this work using the Community Earth System Model version 1.0.5 (CESM1.0.5) with the Community Atmosphere Model version 5.1 (CAM5.1) (referred to as CESM1.0.5/CAM5.1). CAM5.1 includes a simple chemistry that is coupled with a 7-mode prognostic Modal Aerosol Model (MAM7). MAM7 includes classical homogenous nucleation (binary and ternary) and activation nucleation (empirical first-order power law) parameterizations, and a highly simplified inorganic aerosol thermodynamics treatment that only simulates particulate-phase sulfate and ammonium. In this work, a new gas-phase chemistry mechanism based on the 2005 Carbon Bond Mechanism for Global Extension (CB05_GE) and several advanced inorganic aerosol treatments for condensation of volatile species, ion-mediated nucleation (IMN), and explicit inorganic aerosol thermodynamics for sulfate, ammonium, nitrate, sodium, and chloride have been incorporated into CESM/CAM5.1-MAM7. Compared to the simple gas-phase chemistry, CB05_GE can predict many more gaseous species, and thus could improve model performance for PM2.5, PM10, PM components, and some PM gaseous precursors such as SO2 and NH3 in several regions as well as aerosol optical depth (AOD) and cloud properties (e.g., cloud fraction (CF), cloud droplet number concentration (CDNC), and shortwave cloud forcing, SWCF) on the global scale. The modified condensation and aqueous-phase chemistry could further improve the prediction of additional variables such as HNO3, NO2, and O3 in some regions, and new particle formation rate (J) and AOD on the global scale. IMN can improve the prediction of secondary PM2

  19. Laboratory Scoping Tests Of Decontamination Of Hanford Waste Treatment Plant Low Activity Waste Off-Gas Condensate Simulant

    SciTech Connect

    Taylor-Pashow, Kathryn M.; Nash, Charles A.; Crawford, Charles L.; McCabe, Daniel J.; Wilmarth, William R.

    2014-01-21

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task seeks to examine the potential treatment of this stream to remove radionuclides and subsequently disposition the decontaminated stream elsewhere, such as the Effluent Treatment Facility (ETF), for example. The treatment process envisioned is very similar to that used for the Actinide Removal Process (ARP) that has been operating for years at the Savannah River Site (SRS), and focuses on using mature radionuclide removal technologies that are also

  20. Hydrogen production from food wastes and gas post-treatment by CO{sub 2} adsorption

    SciTech Connect

    Redondas, V.; Gomez, X.; Garcia, S.; Pevida, C.; Rubiera, F.; Moran, A.; Pis, J.J.

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer The dark fermentation process of food wastes was studied over an extended period. Black-Right-Pointing-Pointer Decreasing the HRT of the process negatively affected the specific gas production. Black-Right-Pointing-Pointer Adsorption of CO{sub 2} was successfully attained using a biomass type activated carbon. Black-Right-Pointing-Pointer H{sub 2} concentration in the range of 85-95% was obtained for the treated gas-stream. - Abstract: The production of H{sub 2} by biological means, although still far from being a commercially viable proposition, offers great promise for the future. Purification of the biogas obtained may lead to the production of highly concentrated H{sub 2} streams appropriate for industrial application. This research work evaluates the dark fermentation of food wastes and assesses the possibility of adsorbing CO{sub 2} from the gas stream by means of a low cost biomass-based adsorbent. The reactor used was a completely stirred tank reactor run at different hydraulic retention times (HRTs) while the concentration of solids of the feeding stream was kept constant. The results obtained demonstrate that the H{sub 2} yields from the fermentation of food wastes were affected by modifications in the hydraulic retention time (HRT) due to incomplete hydrolysis. The decrease in the duration of fermentation had a negative effect on the conversion of the substrate into soluble products. This resulted in a lower amount of soluble substrate being available for metabolisation by H{sub 2} producing microflora leading to a reduction in specific H{sub 2} production. Adsorption of CO{sub 2} from a gas stream generated from the dark fermentation process was successfully carried out. The data obtained demonstrate that the column filled with biomass-derived activated carbon resulted in a high degree of hydrogen purification. Co-adsorption of H{sub 2}S onto the activated carbon also took place, there being no evidence of H

  1. Ab initio treatment of gas phase GeO2+ doubly charged ion

    NASA Astrophysics Data System (ADS)

    Mogren Al Mogren, M.; Ben Abdallah, D.; Hochlaf, M.

    2015-01-01

    Using multi reference configuration interaction methodology in connection with a large basis set, we show that GeO2+ is a metastable species either in the ground or in the electronically excited states. This confirms the observation of this dication in gas phase by mass spectrometry. In addition, we derived a set of accurate spectroscopic terms for GeO2+ bound states. At the MRCI/aug-cc-pV5Z level of theory, the adiabatic double ionization energy of GeO is computed to be ∼28.93 eV.

  2. Reduction of VOCs in flue gas from coal combustion by electron beam treatment

    NASA Astrophysics Data System (ADS)

    Chmielewski, A. G.; Ostapczuk, A.; Zimek, Z.; Licki, J.; Kubica, K.

    2002-03-01

    Coal combustion is one of the biggest sources of VOCs, which are emitted with various concentrations, polynuclear aromatic hydrocarbons (PAH) are known as the most dangerous, and among them, e.g. benzo(a)pyrene C 20H 12, benzo(g,h,I)perylene C 22H 12 or dibenzo(a,h)anthracene C 22H 14 are the most toxic according to EPA. Recent years have brought new regulations concerning PAH emission, and European countries have signed an international treaty, covering PAH emission. Tests at the pilot plant constructed at a coal-fired power station were performed with the purpose of estimating the influence of electron beam on VOCs present in flue gas, during SO 2 and NO x removal. The influence of electron beam on the global toxicity factor of flue gas has been analysed. In the presence of ammonia, the concentrations of some PAHs were lower than that without ammonia. The removal efficiencies have been ranged from 40% up to 98%.

  3. Removal of hydrogen sulfide gas and landfill leachate treatment using coal bottom ash.

    PubMed

    Lin, C Y; Hesu, P H; Yang, D H

    2001-06-01

    Coal bottom ashes produced from three thermal power plants were used in column and batch experiments to investigate the adsorption capacity of the coal ash. Hydrogen sulfide and leachates collected from three sanitary landfill sites were used as adsorbate gas and solutions, respectively. Experimental results showed that coal bottom ash could remove H2S from waste gas or reduce the concentrations of various pollutants in the leachate. Each gram of bottom ash could remove up to 10.5 mg of H2S. In treating the landfill leachate, increasing ash dosage increased the removal efficiency but decreased the adsorption amount per unit mass of ash. For these tested ashes, the removal efficiencies of chemical oxygen demand (COD), NH3-N, total Kjeldhal nitrogen (TKN), P, Fe3+, Mn2+, and Zn2+ were 36.4-50, 24.2-39.4, 27.0-31.1, 82.2-92.9, 93.8-96.5, 93.7-95.4, and 80.5-82.2%, respectively; the highest adsorption capacities for those parameters were 3.5-5.6, 0.22-0.63, 0.36-0.45, 0.027-0.034, 0.050-0.053, 0.029-0.032, and 0.006 mg/g of bottom ash, respectively. The adsorption of pollutants in the leachate conformed to Freundlich's adsorption model.

  4. Integrated treatment process using a natural Wyoming clinoptilolite for remediating produced waters from coalbed natural gas operations

    USGS Publications Warehouse

    Zhao, H.; Vance, G.F.; Urynowicz, M.A.; Gregory, R.W.

    2009-01-01

    Coalbed natural gas (CBNG) development in western U.S. states has resulted in an increase in an essential energy resource, but has also resulted in environmental impacts and additional regulatory needs. A concern associated with CBNG development relates to the production of the copious quantities of potentially saline-sodic groundwater required to recover the natural gas, hereafter referred to as CBNG water. Management of CBNG water is a major environmental challenge because of its quantity and quality. In this study, a locally available Na-rich natural zeolite (clinoptilolite) from Wyoming (WY) was examined for its potential to treat CBNG water to remove Na+ and lower the sodium adsorption ratio (SAR, mmol1/2 L- 1/2). The zeolite material was Ca-modified before being used in column experiments. Column breakthrough studies indicated that a metric tonne (1000??kg) of Ca-WY-zeolite could be used to treat 60,000??L of CBNG water in order to lower SAR of the CBNG water from 30 to an acceptable level of 10??mmol1/2 L- 1/2. An integrated treatment process using Na-WY-zeolite for alternately treating hard water and CBNG water was also examined for its potential to treat problematic waters in the region. Based on the results of this study, use of WY-zeolite appears to be a cost-effective water treatment technology for maximizing the beneficial use of poor-quality CBNG water. Ongoing studies are evaluating water treatment techniques involving infiltration ponds lined with zeolite. ?? 2008 Elsevier B.V. All rights reserved.

  5. Feasibility and Treatment of Oil and Gas Produced Water as a Medium for Nannochloropsis Salina cultivation

    SciTech Connect

    Sullivan, Enid J.; Dean, Cynthia A.; Yoshida, Thomas M.; Steichen, Seth A.; Laur, Paul A.; Visolay, Alfonz

    2012-06-06

    Some conclusions of this paper are: (1) How much PW is available - (a) Lots, but probably not enough to support the largest estimates of algae production needed, (b) Diluent water is likely needed to support cultivation in some cases, (c) An assessment of how much PW is really available for use is needed; (2) Where is it available - (a) In many places near other resources (land, CO{sub 2}, sunlight, nutrients) and infrastructure (pipelines, refineries, disposal operations/wells); (3) Is the water chemistry acceptable for use - (a) Yes, in many cases with minimal treatment, (b) Additional constituents of value exist in PW for media; (4) Does it need treatment prior to use - (a) Yes, it may often need treatment for organics, some metals, and biological contaminants, (b) Source control and monitoring can reduce need for treatment; (5) How much does it cost to treat it - (a) If desalination is not needed, from <$0.01-$0.60 per m3 is a starting estimate; and (6) Can you grow algae in it - (a) Yes, but we need more experimentation to optimize field conditions, media mixing, and algae types.

  6. USING CMAQ-AIM TO EVALUATE THE GAS-PARTICLE PARTITIONING TREATMENT IN CMAQ

    EPA Science Inventory

    The Community Multi-scale Air Quality model (CMAQ) aerosol component utilizes a modal representation, where the size distribution is represented as a sum of three lognormal modes. Though the aerosol treatment in CMAQ is quite advanced compared to other operational air quality mo...

  7. ESTIMATES OF GLOBAL GREENHOUSE GAS EMISSIONS FROM INDUSTRIAL AND DOMESTIC WASTEWATER TREATMENT

    EPA Science Inventory

    The report summarizes the findings of field tests and provides emission factors for methane (CH4) and nitrous oxide (N2O) from wastewater treatment (WWT). It also includes country-specific activity data on industrial and domestic WWT which were used to develop country-specific em...

  8. Hydrogen production from food wastes and gas post-treatment by CO2 adsorption.

    PubMed

    Redondas, V; Gómez, X; García, S; Pevida, C; Rubiera, F; Morán, A; Pis, J J

    2012-01-01

    The production of H(2) by biological means, although still far from being a commercially viable proposition, offers great promise for the future. Purification of the biogas obtained may lead to the production of highly concentrated H(2) streams appropriate for industrial application. This research work evaluates the dark fermentation of food wastes and assesses the possibility of adsorbing CO(2) from the gas stream by means of a low cost biomass-based adsorbent. The reactor used was a completely stirred tank reactor run at different hydraulic retention times (HRTs) while the concentration of solids of the feeding stream was kept constant. The results obtained demonstrate that the H(2) yields from the fermentation of food wastes were affected by modifications in the hydraulic retention time (HRT) due to incomplete hydrolysis. The decrease in the duration of fermentation had a negative effect on the conversion of the substrate into soluble products. This resulted in a lower amount of soluble substrate being available for metabolisation by H(2) producing microflora leading to a reduction in specific H(2) production. Adsorption of CO(2) from a gas stream generated from the dark fermentation process was successfully carried out. The data obtained demonstrate that the column filled with biomass-derived activated carbon resulted in a high degree of hydrogen purification. Co-adsorption of H(2)S onto the activated carbon also took place, there being no evidence of H(2)S present in the bio-H(2) exiting the column. Nevertheless, the concentration of H(2)S was very low, and this co-adsorption did not affect the CO(2) capture capacity of the activated carbon.

  9. LABORATORY OPTIMIZATION TESTS OF TECHNETIUM DECONTAMINATION OF HANFORD WASTE TREATMENT PLANT LOW ACTIVITY WASTE OFF-GAS CONDENSATE SIMULANT

    SciTech Connect

    Taylor-Pashow, K.; Nash, C.; McCabe, D.

    2014-09-29

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility again. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable de-coupled operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste. This LAW Off-Gas Condensate stream contains components that are volatile at melter temperatures and are problematic for the glass waste form. Because this stream recycles within WTP, these components accumulate in the Condensate stream, exacerbating their impact on the number of LAW glass containers that must be produced. Approximately 32% of the sodium in Supplemental LAW comes from glass formers used to make the extra glass to dilute the halides to acceptable concentrations in the LAW glass, and diverting the stream reduces the halides in the recycled Condensate and is a key outcome of this work. Additionally, under possible scenarios where the LAW vitrification facility commences operation prior to the WTP Pretreatment facility, identifying a disposition path becomes vitally important. This task examines the potential treatment of this stream to remove radionuclides and subsequently disposition the decontaminated stream elsewhere, such as the Effluent Treatment Facility (ETF), for example. The treatment process envisioned is very similar to that used for the Actinide Removal Process (ARP) that has been operating for years at the Savannah River Site (SRS), and focuses on using mature radionuclide removal technologies that are also

  10. Life-Cycle Energy Use and Greenhouse Gas Emissions of a Building-Scale Wastewater Treatment and Nonpotable Reuse System.

    PubMed

    Hendrickson, Thomas P; Nguyen, Mi T; Sukardi, Marsha; Miot, Alexandre; Horvath, Arpad; Nelson, Kara L

    2015-09-01

    Treatment and water reuse in decentralized systems is envisioned to play a greater role in our future urban water infrastructure due to growing populations and uncertainty in quality and quantity of traditional water resources. In this study, we utilized life-cycle assessment (LCA) to analyze the energy consumption and greenhouse gas (GHG) emissions of an operating Living Machine (LM) wetland treatment system that recycles wastewater in an office building. The study also assessed the performance of the local utility's centralized wastewater treatment plant, which was found to be significantly more efficient than the LM (79% less energy, 98% less GHG emissions per volume treated). To create a functionally equivalent comparison, the study developed a hypothetical scenario in which the same LM design flow is recycled via centralized infrastructure. This comparison revealed that the current LM has energy consumption advantages (8% less), and a theoretically improved LM design could have GHG advantages (24% less) over the centralized reuse system. The methodology in this study can be applied to other case studies and scenarios to identify conditions under which decentralized water reuse can lower GHG emissions and energy use compared to centralized water reuse when selecting alternative approaches to meet growing water demands. PMID:26230383

  11. Life-Cycle Energy Use and Greenhouse Gas Emissions of a Building-Scale Wastewater Treatment and Nonpotable Reuse System.

    PubMed

    Hendrickson, Thomas P; Nguyen, Mi T; Sukardi, Marsha; Miot, Alexandre; Horvath, Arpad; Nelson, Kara L

    2015-09-01

    Treatment and water reuse in decentralized systems is envisioned to play a greater role in our future urban water infrastructure due to growing populations and uncertainty in quality and quantity of traditional water resources. In this study, we utilized life-cycle assessment (LCA) to analyze the energy consumption and greenhouse gas (GHG) emissions of an operating Living Machine (LM) wetland treatment system that recycles wastewater in an office building. The study also assessed the performance of the local utility's centralized wastewater treatment plant, which was found to be significantly more efficient than the LM (79% less energy, 98% less GHG emissions per volume treated). To create a functionally equivalent comparison, the study developed a hypothetical scenario in which the same LM design flow is recycled via centralized infrastructure. This comparison revealed that the current LM has energy consumption advantages (8% less), and a theoretically improved LM design could have GHG advantages (24% less) over the centralized reuse system. The methodology in this study can be applied to other case studies and scenarios to identify conditions under which decentralized water reuse can lower GHG emissions and energy use compared to centralized water reuse when selecting alternative approaches to meet growing water demands.

  12. Turgor pressure responses of a gram-negative bacterium to antibiotic treatment, measured by collapse of gas vesicles.

    PubMed

    Pinette, M F; Koch, A L

    1988-03-01

    The internal hydrostatic pressure of Ancylobacter aquaticus was measured by collapsing the gas vesicles with an externally applied pressure. Turgor pressure was measured in conjunction with various antibiotic treatments to elucidate some aspects of the biophysics of gram-negative cell wall function. Differences in the effects of these drugs either alone or in combination with other treatments were related to known biochemical activities of these drugs. Our previous work, demonstrating a heterogeneous cellular response to beta-lactam antibodies, was confirmed and extended. Most of the cell wall growth-inhibiting antibiotics resulted in some cells (those in component I) developing a higher pressure, while the remainder (those in component II) lost turgor. Although the fraction of the cells in each component varied a little from subculture to subculture, it did not vary with time or choice of antibiotic treatment. Mecillinam gave a nearly monophasic response. All antibiotics blocking macromolecular synthesis gave monophasic curves. The 50% collapse pressure in some cases, however, was lower higher, or the same as the control.

  13. Process system evaluation-consolidated letters. Volume 1. Alternatives for the off-gas treatment system for the low-level waste vitrification process

    SciTech Connect

    Peurrung, L.M.; Deforest, T.J; Richards, J.R.

    1996-03-01

    This report provides an evaluation of alternatives for treating off-gas from the low-level waste (LLW) melter. The study used expertise obtained from the commercial nonradioactive off-gas treatment industry. It was assumed that contact maintenance is possible, although the subsequent risk to maintenance personnel was qualitatively considered in selecting equipment. Some adaptations to the alternatives described may be required, depending on the extent of contact maintenance that can be achieved. This evaluation identified key issues for the off-gas system design. To provide background information, technology reviews were assembled for various classifications of off-gas treatment equipment, including off-gas cooling, particulate control, acid gas control, mist elimination, NO{sub x} reduction, and SO{sub 2} removal. An order-of-magnitude cost estimate for one of the off-gas systems considered is provided using both the off-gas characteristics associated with the Joule-heated and combustion-fired melters. The key issues identified and a description of the preferred off-gas system options are provided below. Five candidate treatment systems were evaluated. All of the systems are appropriate for the different melting/feed preparations currently being considered. The lowest technical risk is achieved using option 1, which is similar to designs for high-level waste (HLW) vitrification in the Hanford Waste Vitrification Project (HWVP) and the West Valley. Demonstration Project. Option 1 uses a film cooler, submerged bed scrubber (SBS), and high-efficiency mist eliminator (HEME) prior to NO{sub x} reduction and high-efficiency particulate air (HEPA) filtration. However, several advantages were identified for option 2, which uses high-temperature filtration. Based on the evaluation, option 2 was identified as the preferred alternative. The characteristics of this option are described below.

  14. [Diversity analysis of desulfuration bacterium from the oxidation ditch of city sewage treatment plant with SO2 gas].

    PubMed

    Huang, Bing; Zhang, Shi-Ling; Zhang, Jiang-Hong; Ao, Yong; Shi, Zhe

    2011-07-01

    A group of removing SO2 bacterium was obtained from the oxidation ditch of city sewage treatment plant by inductive domestication over 6 d with low concentration SO2 gas, and they have an ability with biodegradation rate of 888 mg x (L x h)(-1) and a degradation efficiency of 85% during 1.5 h for SO2 dissolved in water with their synergy. The clone library and two phylogenetic trees of the removing SO2 bacterium communities were obtained based on 16S rRNA DNA comparison by DNA extraction of the sample and in situ polymerase chain reaction (PCR). The phylogenetic analysis showed that 8 dominant desulfuration bacterium occupy about 69% of all removing SO2 bacterium, and some of them have a kindred with discovered desulfuration bacterium but not homogeneity, and there are four belong to alpha-Proteobacteria, another four belong to beta-Proteobacteria in them. The gene information about 16S rRNA sequence of the dominant desulfuration bacteria and domestication method provide a basic of looking for or domesticating removing SO2 bacterium for development microbial desulfurization technology of contained SO2 tail gas.

  15. The use of gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry to demonstrate progesterone treatment in bovines.

    PubMed

    Janssens, Geert; Mangelinckx, Sven; Courtheyn, Dirk; De Kimpe, Norbert; Matthijs, Bert; Le Bizec, Bruno

    2016-06-01

    Currently, no analytical method is available to demonstrate progesterone administration in biological samples collected in rearing animals, and therefore, tracking the abuse of this popular growth promoter is arduous. In this study, a method is presented to reveal progesterone (PG) treatment on the basis of carbon isotope measurement of 5β-pregnane-3α, 20α-diol (BAA-PD), a major PG metabolite excreted in bovine urine, by gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry (GC-MS/C/IRMS). 5-Androstene-3β,17α-diol (AEdiol) is used as endogenous reference compound. Intermediate precisions (n=11) of 0.56‰ and 0.68‰ have been determined for AEdiol and BAA-PD, respectively. The analytical method was used for the very first time to successfully differentiate urine samples collected in treated and untreated animals.

  16. Improvement and further development in CESM/CAM5: gas-phase chemistry and inorganic aerosol treatments

    NASA Astrophysics Data System (ADS)

    He, J.; Zhang, Y.

    2013-10-01

    Gas-phase chemistry and subsequent gas-to-particle conversion processes such as new particle formation, condensation, and thermodynamic partitioning have large impacts on air quality, climate, and public health through influencing the amounts and distributions of gaseous precursors and secondary aerosols. Their roles in global air quality and climate are examined in this work using the Community Earth System Model version 1.0.5 (CESM1.0.5) with the Community Atmosphere Model version 5.1 (CAM5.1) (referred to as CESM1.0.5/CAM5.1). CAM5.1 includes a simple chemistry that is coupled with a 7-mode prognostic Modal Aerosol Model (MAM7). MAM7 includes classical homogenous nucleation (binary and ternary) and activation nucleation (empirical first-order power law) parameterizations, and a highly-simplified inorganic aerosol thermodynamics treatment that only simulates sulfate (SO42-) and ammonium (NH4+). In this work, a new gas-phase chemistry mechanism based on the 2005 Carbon Bond Mechanism for Global Extension (CB05_GE) and several advanced inorganic aerosol treatments for condensation of volatile species, ion-mediated nucleation (IMN), and explicit inorganic aerosol thermodynamics have been incorporated into CESM/CAM5.1-MAM7. Comparing to the simple gas-phase chemistry, CB05_GE can predict many more gaseous species, and improve model performance for PM2.5, PM10, PM2.5 components, and some PM gaseous precursors such as SO2 and NH3 in several regions, as well as aerosol optical depth (AOD) and cloud properties (e.g., cloud fraction (CF), cloud droplet number concentration (CDNC), and shortwave cloud forcing (SWCF)) on globe. The modified condensation and aqueous-phase chemistry further improves the predictions of additional variables such as HNO3, NO2, and O3 in some regions, and new particle formation rate (J) and AOD over globe. IMN can improve the predictions of secondary PM2.5 components, PM2.5, and PM10 over Europe, as well as AOD and CDNC over globe. The explicit

  17. The use of gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry to demonstrate progesterone treatment in bovines.

    PubMed

    Janssens, Geert; Mangelinckx, Sven; Courtheyn, Dirk; De Kimpe, Norbert; Matthijs, Bert; Le Bizec, Bruno

    2016-06-01

    Currently, no analytical method is available to demonstrate progesterone administration in biological samples collected in rearing animals, and therefore, tracking the abuse of this popular growth promoter is arduous. In this study, a method is presented to reveal progesterone (PG) treatment on the basis of carbon isotope measurement of 5β-pregnane-3α, 20α-diol (BAA-PD), a major PG metabolite excreted in bovine urine, by gas chromatography-mass spectrometry/combustion/isotope ratio mass spectrometry (GC-MS/C/IRMS). 5-Androstene-3β,17α-diol (AEdiol) is used as endogenous reference compound. Intermediate precisions (n=11) of 0.56‰ and 0.68‰ have been determined for AEdiol and BAA-PD, respectively. The analytical method was used for the very first time to successfully differentiate urine samples collected in treated and untreated animals. PMID:27157423

  18. [Rheoencephlographic studies during general halothane anesthesia and laughing gas in stomatological treatment of children at the out-patient department].

    PubMed

    Novkova, A; Săbev, K

    1989-01-01

    Thirty two children, aged from 6 to 14 were studied by the rheoencephalographic method during general halothane and laughing gas anesthesia, stomatologically treated under out-patient department conditions. The quantitative analysis of the rheoencephalographic curves made of the method of differentia, the data being compared one hour before the general anesthesia, during the stage of surgical anesthesia and one hour after it. Statistically significant data were established showing pulse supply improvement and reduction of vascular tone of the brain blood vessels during general anesthesia and one hour after it. The expedience of the application of the rheoencephalographic method during general anesthesia is stressed upon as well as the potentialities of its application in the stomatological practice. The positive qualities of the method of general anesthesia applied for the stomatological treatment of children under out-patient department conditions are confirmed. PMID:2520867

  19. Gas Chromatography Analyses for Trihalomethanes: An Experiment Illustrating Important Sources of Disinfection By-Products in Water Treatment

    NASA Astrophysics Data System (ADS)

    Olson, Terese M.; Gonzalez, Alicia C.; Vasquez, Victor R.

    2001-09-01

    Chlorination processes are an important disinfection strategy in drinking water treatment. Side-reactions of chlorine species with naturally present organic matter, however, are known to produce toxic disinfection by-products (DBPs). One important class of DBPs is trihalomethanes. This experiment demonstrates how trihalomethanes form in a chlorination process by using a model substrate, resorcinol, to mimic the reactive moieties present in natural organic matter. To further simulate how bromo-substituted trihalomethanes are typically obtained in a chlorination process, bromide is also added to the resorcinol solution. Reaction pathways and yields for the formation of trihalomethanes are discussed. The experiment provides a meaningful example of gas chromatography analyses of mixtures of environmentally relevant compounds and is suitable for an undergraduate junior/senior level or graduate environmental chemistry course.

  20. The effect of microbubbles on gas-liquid mass transfer coefficient and degradation rate of COD in wastewater treatment.

    PubMed

    Yao, Kangning; Chi, Yong; Wang, Fei; Yan, Jianhua; Ni, Mingjiang; Cen, Kefa

    2016-01-01

    A commonly used aeration device at present has the disadvantages of low mass transfer rate because the generated bubbles are several millimeters in diameter which are much bigger than microbubbles. Therefore, the effect of a microbubble on gas-liquid mass transfer and wastewater treatment process was investigated. To evaluate the effect of each bubble type, the volumetric mass transfer coefficients for microbubbles and conventional bubbles were determined. The volumetric mass transfer coefficient was 0.02905 s(-1) and 0.02191 s(-1) at a gas flow rate of 0.67 L min(-1) in tap water for microbubbles and conventional bubbles, respectively. The degradation rate of simulated municipal wastewater was also investigated, using aerobic activated sludge and ozone. Compared with the conventional bubble generator, the chemical oxygen demand (COD) removal rate was 2.04, 5.9, 3.26 times higher than those of the conventional bubble contactor at the same initial COD concentration of COD 200 mg L(-1), 400 mg L(-1), and 600 mg L(-1), while aerobic activated sludge was used. For the ozonation process, the rate of COD removal using microbubble generator was 2.38, 2.51, 2.89 times of those of the conventional bubble generator. Based on the results, the effect of initial COD concentration on the specific COD degradation rate were discussed in different systems. Thus, the results revealed that microbubbles could enhance mass transfer in wastewater treatment and be an effective method to improve the degradation of wastewater. PMID:27120652

  1. Greenhouse gas emission reduction and environmental quality improvement from implementation of aerobic waste treatment systems in swine farms.

    PubMed

    Vanotti, M B; Szogi, A A; Vives, C A

    2008-01-01

    Trading of greenhouse gas (GHG) emission reductions is an attractive approach to help producers implement cleaner treatment technologies to replace current anaerobic lagoons. Our objectives were to estimate greenhouse gas (GHG) emission reductions from implementation of aerobic technology in USA swine farms. Emission reductions were calculated using the approved United Nations framework convention on climate change (UNFCCC) methodology in conjunction with monitoring information collected during full-scale demonstration of the new treatment system in a 4360-head swine operation in North Carolina (USA). Emission sources for the project and baseline manure management system were methane (CH4) emissions from the decomposition of manure under anaerobic conditions and nitrous oxide (N2O) emissions during storage and handling of manure in the manure management system. Emission reductions resulted from the difference between total project and baseline emissions. The project activity included an on-farm wastewater treatment system consisting of liquid-solid separation, treatment of the separated liquid using aerobic biological N removal, chemical disinfection and soluble P removal using lime. The project activity was completed with a centralized facility that used aerobic composting to process the separated solids. Replacement of the lagoon technology with the cleaner aerobic technology reduced GHG emissions 96.9%, from 4972 tonnes of carbon dioxide equivalents (CO2-eq) to 153 tonnes CO2-eq/year. Total net emission reductions by the project activity in the 4360-head finishing operation were 4776.6 tonnes CO2-eq per year or 1.10 tonnes CO2-eq/head per year. The dollar value from implementation of this project in this swine farm was US$19,106/year using current Chicago Climate Exchange trading values of US$4/t CO2. This translates into a direct economic benefit to the producer of US$1.75 per finished pig. Thus, GHG emission reductions and credits can help compensate for the

  2. Influence of hydrophobic treatment on the structure of compressed gas diffusion layers

    NASA Astrophysics Data System (ADS)

    Tötzke, C.; Gaiselmann, G.; Osenberg, M.; Arlt, T.; Markötter, H.; Hilger, A.; Kupsch, A.; Müller, B. R.; Schmidt, V.; Lehnert, W.; Manke, I.

    2016-08-01

    Carbon fiber based felt materials are widely used as gas diffusion layer (GDL) in fuel cells. Their transport properties can be adjusted by adding hydrophobic agents such as polytetrafluoroethylene (PTFE). We present a synchrotron X-ray tomographic study on the felt material Freudenberg H2315 with different PTFE finishing. In this study, we analyze changes in microstructure and shape of GDLs at increasing degree of compression which are related to their specific PTFE load. A dedicated compression device mimicking the channel-land pattern of the flowfield is used to reproduce the inhomogeneous compression found in a fuel cell. Transport relevant geometrical parameters such as porosity, pore size distribution and geometric tortuosity are calculated and consequences for media transport discussed. PTFE finishing results in a marked change of shape of compressed GDLs: surface is smoothed and the invasion of GDL fibers into the flow field channel strongly mitigated. Furthermore, the PTFE impacts the microstructure of the compressed GDL. The number of available wide transport paths is significantly increased as compared to the untreated material. These changes improve the transport capacity liquid water through the GDL and promote the discharge of liquid water droplets from the cell.

  3. Release model for in situ vitrification large-field test off-gas treatment system

    SciTech Connect

    Pafford, D.J.; Tung, V.X.

    1992-03-01

    A conceptual model for the vapor and aerosol transport and deposition in the in situ vitrification large-field test off-gas system (OGS) has been developed. This model can be used to predict the emissions from the OGS under normal and off-normal conditions. Results generated by the model can be used to evaluate design and/or procedural modifications, define tests, and predict results. The OGS vapor and aerosol transport and deposition is modeled using the PULSE/MOD-ISV/VER 1.0.0 developmental computer code. Input data requirements for this code include the specific geometries of the OGS components; the composition, rate, and temperature of the vapors and aerosols entering the OGS; and the OGS component surface temperatures or heat fluxes. Currently, not all of these model inputs are available. Therefore, conceptual input parameters are developed. Using this input data, preliminary calculations with the code have been performed. These calculations include a demonstration that the code predicts convergent results, a comparison of predicted results with performance data for one of the OGS components, and a preliminary sensitivity study of the complete model.

  4. The effect of zeolite treatment by acids on sodium adsorption ratio of coal seam gas water.

    PubMed

    Wang, Xiaoyu; Ozdemir, Orhan; Hampton, Marc A; Nguyen, Anh V; Do, Duong D

    2012-10-15

    Many coal seam gas (CSG) waters contain a sodium ion concentration which is too high relative to calcium and magnesium ions for environment acceptance. Natural zeolites can be used as a cheap and effective method to control sodium adsorption ratio (SAR, which is a measure of the relative preponderance of sodium to calcium and magnesium) due to its high cation exchange capacity. In this study, a natural zeolite from Queensland was examined for its potential to treat CSG water to remove sodium ions to lower SAR and reduce the pH value. The results demonstrate that acid activated zeolite at 30%wt solid ratio can reduce the sodium content from 563.0 to 182.7 ppm; the pH from 8.74 to 6.95; and SAR from 70.3 to 18.5. Based on the results of the batch experiments, the sodium adsorption capacity of the acid-treated zeolite is three times greater than that of the untreated zeolite. Both the untreated and acid-treated zeolite samples were characterized using zeta potential, surface characterization, DTA/TG and particle size distribution in order to explain their adsorption behaviours.

  5. The effect of zeolite treatment by acids on sodium adsorption ratio of coal seam gas water.

    PubMed

    Wang, Xiaoyu; Ozdemir, Orhan; Hampton, Marc A; Nguyen, Anh V; Do, Duong D

    2012-10-15

    Many coal seam gas (CSG) waters contain a sodium ion concentration which is too high relative to calcium and magnesium ions for environment acceptance. Natural zeolites can be used as a cheap and effective method to control sodium adsorption ratio (SAR, which is a measure of the relative preponderance of sodium to calcium and magnesium) due to its high cation exchange capacity. In this study, a natural zeolite from Queensland was examined for its potential to treat CSG water to remove sodium ions to lower SAR and reduce the pH value. The results demonstrate that acid activated zeolite at 30%wt solid ratio can reduce the sodium content from 563.0 to 182.7 ppm; the pH from 8.74 to 6.95; and SAR from 70.3 to 18.5. Based on the results of the batch experiments, the sodium adsorption capacity of the acid-treated zeolite is three times greater than that of the untreated zeolite. Both the untreated and acid-treated zeolite samples were characterized using zeta potential, surface characterization, DTA/TG and particle size distribution in order to explain their adsorption behaviours. PMID:22841594

  6. Treatment of waste gas containing low concentration of dimethyl sulphide in a high performance biotrickling filter.

    PubMed

    Giri, Balendu Shekher; Juwarkar, Asha; Mudliar, S N; Pandey, R A

    2013-11-01

    A bench-scale biotrickling filter was operated in the laboratory for the treatment of dimethyl sulphide (DMS). The biotrickling filter was packed with pre-sterilized polyurethane foam and seeded with biomass developed from garden soil enriched with DMS. The biotrickling filter was operated for the generation of process parameters. The biotrickling filter could remove an average removal efficiency of 40.95% at an effective bed contact time of 84 sec with an average loading rate of 0.56 mg/m3/h. Evaluation of microbiological status of the biotrickling filter indicated the presence of other bacterial cultures viz. Paenibacillus polymyxa, and Bacillus megaterium, besides Bacillus sphaericus.

  7. Sequential chemical treatment of radium species in TENORM waste sludge produced from oil and natural gas production.

    PubMed

    El Afifi, E M; Awwad, N S; Hilal, M A

    2009-01-30

    This paper is dedicated to the treatment of sludge occurring in frame of the Egyptian produced from oil and gas production. The activity levels of three radium isotopes: Ra-226 (of U-series), Ra-228 and Ra-224 (of Th-series) in the solid TENORM waste (sludge) were first evaluated and followed by a sequential treatment for all radium species (fractions) presented in TENORM. The sequential treatment was carried out based on two approaches 'A' and 'B' using different chemical solutions. The results obtained indicate that the activity levels of all radium isotopes (Ra-226, Ra-228 and Ra-224) of the environmental interest in the TENORM waste sludge were elevated with regard to exemption levels established by IAEA [International Atomic Energy Agency (IAEA), International basic safety standards for the protection against ionizing radiation and for the safety of radiation sources. GOV/2715/Vienna, 1994]. Each approach of the sequential treatment was performed through four steps using different chemical solutions to reduce the activity concentration of radium in a large extent. Most of the leached radium was found as an oxidizable Ra species. The actual removal % leached using approach B was relatively efficient compared to A. It is observed that the actual removal percentages (%) of Ra-226, Ra-228 and Ra-224 using approach A are 78+/-2.8, 64.8+/-4.1 and 76.4+/-5.2%, respectively. Whereas in approach A, the overall removal % of Ra-226, Ra-228 and Ra-228 was increased to approximately 91+/-3.5, 87+/-4.1 and 90+/-6.2%, respectively.

  8. Improved ultrasonic-based sample treatment for the screening of anabolic steroids by gas chromatography/mass spectrometry.

    PubMed

    Galesio, M; Rial-Otero, R; Simal-Gándara, J; de la Torre, X; Botrè, F; Capelo-Martínez, J L

    2010-08-30

    A rapid sample treatment procedure for the gas chromatography/mass spectrometry (GC/MS) determination of anabolic steroids in human urine has been developed. The new procedure makes use of ultrasonic energy to reduce reaction times and increase the overall sensitivity. The following variables affecting the performance of the ultrasonic treatment were optimised: (i) time, (ii) device, (iii) frequency, and (iv) temperature. It was found that, under an ultrasonic field, the hydrolysis of conjugated steroids with beta-glucuronidase from Escherichia coli K12 was possible with a treatment time of 10 min. The accuracy and precision of the ultrasonic method were found to be in agreement with those achieved with the conventional thermal conductivity procedure (Student's t-test; p = 0.05, n = 10). After the enzymatic hydrolysis, the derivatisation of the target compounds with trimethylsilyl (TMS) reagent, methyl-N-trimethylsilyltrifluoroacetamide (MSTFA)/NH(4)I/dithioerythritol (DTE) (1000:2:4, v/w/w), was also accelerated using ultrasonic energy. In order to test the applicability of the use of ultrasonic energy in the acceleration of the derivatisation reaction with TMS, the classic method of thermal conductivity was applied for comparative purposes to a pool of 35 androgenic anabolic steroids (AAS) and/or their metabolites. The results demonstrated that after 3 min of sonication in a Sonoreactor device (50% amplitude), 19 of the 35 compounds studied showed similar reaction yield to those obtained with the classic procedure requiring 30 min (Student's t-test; p = 0.05, n = 5); 13 increased to higher silylation yields; and for the steroids 1-testosterone, danazol and etiocholanolone-D5, the same results were obtained using a sonication time of 5 min.The overall applicability of the ultrasonic-based sample treatment method is shown by the analysis of five urine samples. The results are similar to those achieved by the routine procedure. The new method is fast, robust, and

  9. Identification of a non-pathogenic surrogate organism for chlorine dioxide (ClO2) gas treatment.

    PubMed

    Kim, Jeong-Mok; Linton, Richard H

    2008-06-01

    The identification of non-pathogenic surrogate microorganisms is beneficial for determining and validating the efficacy of antimicrobial treatments in food manufacturing environments. A surrogate organism was identified to aid in the decontamination process of fresh produce when treated with chlorine dioxide (ClO(2)) gas. Thirty-two known strains of pathogenic and non-pathogenic microorganisms and seven unknown microbial isolates from mushroom, tomatoes, and strawberries were evaluated. The primary goal was to find alternative non-pathogenic organisms that had an equal or higher resistance compared to Escherichia coli O157:H7, Salmonella spp., and Listeria monocytogenes. Among the strains tested, MR1 (mushroom isolate), E. coli O157:H7 C7927, E. coli O157:H7 204P, STB2 (strawberry isolate), and vegetative cells of Bacillus cereus 232 in wet inoculum were found to be the most resistant to gaseous ClO(2) treatment at 0.3 mg/l for 1 min and D-values at 0.3 mg/l ClO(2) were 3.53, 1.95, 1.72, 1.68, and 1.57 min, respectively. For identification, the MR1 and STB2 strains were identified using a Ribotyper with the EcoRI restriction enzyme of 16S rDNA sequence. MR1 was identified as Hafnia alvei with a similarity value of 94% using the ribotype pattern and with a 93.6% similarity using an API 20E strip, and with a 99% similarity using 16S rDNA analysis. The Ped-2E9-based cytotoxicity assay was conducted for the MRI strain extracellular toxin and whole cell toxicity and did not show cytotoxicity. Analysis, using multiplex PCR, was performed to verify absence of the eaeA gene. H. alvei is a suitable non-pathogenic surrogate, with higher resistance to ClO(2) gas compared to pathogens studied, that may be useful to establish optimum conditions of ClO(2) gas decontamination systems.

  10. Step-feed biofiltration: a low cost alternative configuration for off-gas treatment.

    PubMed

    Estrada, José M; Quijano, Guillermo; Lebrero, Raquel; Muñoz, Raúl

    2013-09-01

    Clogging due to biomass accumulation and the loss of structural stability of the packing media are common operational drawbacks of standard gas biofiltration inherent to the traditional biofilter design, which result in prohibitive pressure drop buildups and media channeling. In this work, an innovative step-feed biofilter configuration, with the air emission supplied in either two or three locations along the biofilter height, was tested and compared with a standard biofilter using toluene as a model pollutant and two packing materials: compost and perlite. When using compost, the step-feed biofilter supported similar elimination capacities (EC ≈ 80 g m(-3) h(-1)) and CO2 production rates (200 g m(-3) h(-1)) to those achieved in the standard biofilter. However, while the pressure drop in the step-feed system remained below 300 Pa m bed(-1) for 61 days, the standard biofilter reached this value in only 14 days and 4000 Pa m bed(-1) by day 30, consuming 75% more compression energy throughout the entire operational period. Operation with perlite supported lower ECs compared to compost in both the step-feed and standard biofilters (≈ 30 g m(-3) h(-1)), probably due to the high indigenous microbial diversity present in this organic packing material. The step-feed biofilter exhibited 65% lower compression energy requirements than the standard biofilter during operation with perlite, while supporting similar ECs. In brief, step-feed biofiltration constitutes a promising operational strategy capable of drastically reducing the operating costs of biofiltration due to a reduced energy consumption and an increased packing material lifespan. PMID:23764582

  11. Tungsten carbide production from ore concentrates by molten salt-natural gas sparging treatment

    SciTech Connect

    Carnahan, T.G.; Kazonich, G.; Raddatz, A.E.

    1988-01-01

    The U.S. Bureau of Mines conducted a bench-scale study to delineate the important parameters in a three-step process to produce commercial-quality tungsten carbide (WC) directly from tungsten minerals. In the process, tungsten concentrates of wolframite or wolframite and scheelite are decomposed at 1,050{sup 0}C in a molten mixture of NcCl and Na{sub 2}SiO{sub 3} that forms two immiscible phases. Tungsten, as sodium tungstate, reports to the halide phase and is separated from the gangue constituents, which report to the silicate phase. After decanting to separate the two phases, natural gas is sparged into the molten halide phase a 1,070{sup 0}C. Submicrometer crystals of WC are initially produced. These crystals grow into thin triangular-shaped plates up to 100 {mu}m on a side or into popcorn-shaped conglomerates. Sparged WC was examined for its suitability for use in sintered carbide products. In physical evaluations, sparged WC ground to an average particle size of 1.52 {mu}m and compacted with 10 pct Co binder into standard 6-by 22-mm test bars had a density of 14.35 and a Rockwell A hardness of 89.6. This compared favorably with 14.39 and 89.7 respectively, for test bars made from a standard commercial 1.52-{mu}m WC powder. Test bars made from Bureau of Mines WC had no C'' porosity or eta phase.

  12. Step-feed biofiltration: a low cost alternative configuration for off-gas treatment.

    PubMed

    Estrada, José M; Quijano, Guillermo; Lebrero, Raquel; Muñoz, Raúl

    2013-09-01

    Clogging due to biomass accumulation and the loss of structural stability of the packing media are common operational drawbacks of standard gas biofiltration inherent to the traditional biofilter design, which result in prohibitive pressure drop buildups and media channeling. In this work, an innovative step-feed biofilter configuration, with the air emission supplied in either two or three locations along the biofilter height, was tested and compared with a standard biofilter using toluene as a model pollutant and two packing materials: compost and perlite. When using compost, the step-feed biofilter supported similar elimination capacities (EC ≈ 80 g m(-3) h(-1)) and CO2 production rates (200 g m(-3) h(-1)) to those achieved in the standard biofilter. However, while the pressure drop in the step-feed system remained below 300 Pa m bed(-1) for 61 days, the standard biofilter reached this value in only 14 days and 4000 Pa m bed(-1) by day 30, consuming 75% more compression energy throughout the entire operational period. Operation with perlite supported lower ECs compared to compost in both the step-feed and standard biofilters (≈ 30 g m(-3) h(-1)), probably due to the high indigenous microbial diversity present in this organic packing material. The step-feed biofilter exhibited 65% lower compression energy requirements than the standard biofilter during operation with perlite, while supporting similar ECs. In brief, step-feed biofiltration constitutes a promising operational strategy capable of drastically reducing the operating costs of biofiltration due to a reduced energy consumption and an increased packing material lifespan.

  13. Application of dynamic models to estimate greenhouse gas emission by wastewater treatment plants of the pulp and paper industry.

    PubMed

    Ashrafi, Omid; Yerushalmi, Laleh; Haghighat, Fariborz

    2013-03-01

    Greenhouse gas (GHG) emission in wastewater treatment plants of the pulp-and-paper industry was estimated by using a dynamic mathematical model. Significant variations were shown in the magnitude of GHG generation in response to variations in operating parameters, demonstrating the limited capacity of steady-state models in predicting the time-dependent emissions of these harmful gases. The examined treatment systems used aerobic, anaerobic, and hybrid-anaerobic/aerobic-biological processes along with chemical coagulation/flocculation, anaerobic digester, nitrification and denitrification processes, and biogas recovery. The pertinent operating parameters included the influent substrate concentration, influent flow rate, and temperature. Although the average predictions by the dynamic model were only 10 % different from those of steady-state model during 140 days of operation of the examined systems, the daily variations of GHG emissions were different up to ± 30, ± 19, and ± 17 % in the aerobic, anaerobic, and hybrid systems, respectively. The variations of process variables caused fluctuations in energy generation from biogas recovery by ± 6, ± 7, and ± 4 % in the three examined systems, respectively. The lowest variations were observed in the hybrid system, showing the stability of this particular process design. PMID:23179218

  14. Application of dynamic models to estimate greenhouse gas emission by wastewater treatment plants of the pulp and paper industry.

    PubMed

    Ashrafi, Omid; Yerushalmi, Laleh; Haghighat, Fariborz

    2013-03-01

    Greenhouse gas (GHG) emission in wastewater treatment plants of the pulp-and-paper industry was estimated by using a dynamic mathematical model. Significant variations were shown in the magnitude of GHG generation in response to variations in operating parameters, demonstrating the limited capacity of steady-state models in predicting the time-dependent emissions of these harmful gases. The examined treatment systems used aerobic, anaerobic, and hybrid-anaerobic/aerobic-biological processes along with chemical coagulation/flocculation, anaerobic digester, nitrification and denitrification processes, and biogas recovery. The pertinent operating parameters included the influent substrate concentration, influent flow rate, and temperature. Although the average predictions by the dynamic model were only 10 % different from those of steady-state model during 140 days of operation of the examined systems, the daily variations of GHG emissions were different up to ± 30, ± 19, and ± 17 % in the aerobic, anaerobic, and hybrid systems, respectively. The variations of process variables caused fluctuations in energy generation from biogas recovery by ± 6, ± 7, and ± 4 % in the three examined systems, respectively. The lowest variations were observed in the hybrid system, showing the stability of this particular process design.

  15. Light absorption during alkali atom-noble gas atom interactions at thermal energies: a quantum dynamics treatment.

    PubMed

    Pacheco, Alexander B; Reyes, Andrés; Micha, David A

    2006-10-21

    The absorption of light during atomic collisions is treated by coupling electronic excitations, treated quantum mechanically, to the motion of the nuclei described within a short de Broglie wavelength approximation, using a density matrix approach. The time-dependent electric dipole of the system provides the intensity of light absorption in a treatment valid for transient phenomena, and the Fourier transform of time-dependent intensities gives absorption spectra that are very sensitive to details of the interaction potentials of excited diatomic states. We consider several sets of atomic expansion functions and atomic pseudopotentials, and introduce new parametrizations to provide light absorption spectra in good agreement with experimentally measured and ab initio calculated spectra. To this end, we describe the electronic excitation of the valence electron of excited alkali atoms in collisions with noble gas atoms with a procedure that combines l-dependent atomic pseudopotentials, including two- and three-body polarization terms, and a treatment of the dynamics based on the eikonal approximation of atomic motions and time-dependent molecular orbitals. We present results for the collision induced absorption spectra in the Li-He system at 720 K, which display both atomic and molecular transition intensities.

  16. Surface treatment of zinc anodes to improve discharge capacity and suppress hydrogen gas evolution

    NASA Astrophysics Data System (ADS)

    Cho, Yung-Da; Fey, George Ting-Kuo

    The shape change and redistribution of zinc anode material over the electrode during repeated cycling have been identified as the main factors that can limit the life of alkaline zinc-air batteries. Li 2O-2B 2O 3 (lithium boron oxide, LBO) glass with high Li + conductivity and stability can be coated on the surface of zinc powders. The structures of the surface-treated and pristine zinc powders were characterized by XRD, SEM, TEM, ESCA and BET analyses. XRD patterns of LBO-coated zinc powders revealed that the coating did not affect the crystal structure. TEM images of LBO-coated on the zinc particles were compact with an average passivation layer of about 250 nm. The LBO layer can prevent zinc from coming into direct contact with the KOH electrolyte and minimize the side reactions within the batteries. The 0.1 wt.% LBO-coated zinc anode material provided an initial discharge capacity of 1.70 Ah at 0.5 V, while the pristine zinc electrode delivered only 1.57 Ah. A surface-treated zinc electrode can increase discharge capacity, decrease hydrogen evolution reaction, and reduce self-discharge. The results indicated that surface treatment should be effective for improving the comprehensive properties of anode materials for zinc-air batteries.

  17. Determination of alcohol sulfates in wastewater treatment plant influents and effluents by gas chromatography-mass spectrometry.

    PubMed

    Fernández-Ramos, C; Ballesteros, O; Blanc, R; Zafra-Gómez, A; Jiménez-Díaz, I; Navalón, A; Vílchez, J L

    2012-08-30

    In the present paper, we developed an accurate method for the analysis of alcohol sulfates (AS) in wastewater samples from wastewater treatment plant (WWTP) influents and effluents. Although many methodologies have been published in the literature concerning the study of anionic surfactants in environmental samples, at present, the number of analytical methodologies that focus in the determination of AS by gas chromatography in the different environmental compartments is limited. The reason for this is that gas chromatography-mass spectrometry (GC-MS) technique requires a previous hydrolysis reaction followed by derivatization reactions. In the present work, we proposed a new procedure in which the hydrolysis and derivatization reactions take place in one single step and AS are directly converted to trimethylsilyl derivatives. The main factors affecting solid-phase extraction (SPE), hydrolysis/derivatization and GC-MS procedures were accurately optimised. Quantification of the target compounds was performed by using GC-MS in selected ion monitoring (SIM) mode. The limits of detection (LOD) obtained ranged from 0.2 to 0.3 μg L(-1), and limits of quantification (LOQ) from 0.5 to 1.0 μg L(-1), while inter- and intra-day variability was under 5%. A recovery assay was also carried out. Recovery rates for homologues in spiked samples ranged from 96 to 103%. The proposed method was successfully applied for the determination of anionic surfactants in wastewater samples from one WWTP located in Granada (Spain). Concentration levels for the homologues up to 39.4 μg L(-1) in influent and up to 8.1 μg L(-1) in effluent wastewater samples.

  18. Solid waste treatment as a high-priority and low-cost alternative for greenhouse gas mitigation.

    PubMed

    Ayalon, O; Avnimelech, Y; Shechter, M

    2001-05-01

    The increased concern about environmental problems caused by inadequate waste management, as well as the concern about global warming, promotes actions toward a sustainable management of the organic fraction of the waste. Landfills, the most common means to dispose of municipal solid waste (MSW), lead to the conversion of the organic waste to biogas, containing about 50% methane, a very active greenhouse gas (GHG). One unit of methane has a global warming potential of 21 computed for a 100-year horizon or 56 computed for 20 years. The waste sector in Israel contributes 13% of total greenhouse gases (GHG) emissions for a time horizon of 100 years (for a time horizon of 20 years, the waste sector contribution equals to more than 25% of total GHG emissions). The ultimate goal is to minimize the amount of methane (CH4) by converting it to CO2. This can be achieved by physicochemical means (e.g., landfill gas flare, incineration) or by biological processes (e.g., composting, anaerobic digestion). Since the waste in Israel has a high organic material content, it was found that the most cost-effective means to treat the degradable organic components is by aerobic composting (investment of less than US$ 10 to reduce emission of one ton CO2 equivalent per year). Another benefit of this technology is the ability to implement it within a short period. The suggested approach, which should be implemented especially in developing countries, could reduce a significant amount of GHG at relatively low cost and short time. The development of a national policy for proper waste treatment can be a significant means to abate GHG emissions in the short term, enabling a gain in time to develop other means for the long run. In addition, the use of CO2 quotas will credit the waste sector and will promote profitable proper waste management.

  19. Greenhouse Gas (CH4, CO2 and N2O) Emission Levels by Wastewater Treatment Plant (WWTP) Ponds in Brazil

    NASA Astrophysics Data System (ADS)

    Rossete, A. L. M.; Sundefeld Junior, G.; Aparicio, C.; Baldi, G. G.; Montes, C. R.; Piveli, R. P.; Melfi, A. J.

    2015-12-01

    This study measured greenhouse gas emissions (GHG) by Facultative Ponds on Wastewater Treatment Plants. The most studied GHGs include CO2, CH4and N2O. The level of GHG (CO2, CH4 and N2O) emissions by WWTPs in Australian-type stabilization ponds was measured in the city of Lins (22º21'S, 49º50'W), state of São Paulo (SP), Brazil. GHG collection was carried outusing a collection chamber installed at the center of the facultative pond's final third. The effluent's pH and temperature (ET) were registered by probes, and meteorological information regarding air temperature (AT) and solar radiation (SR) were obtained from INMET, Brazil. GHG collection was carried out for 72 consecutive hours in June 2014, on an hourly basis, once every 5 minutes, for the first 30 minutes, and once every 10 minutes from 30 to 50 minutesand subsequently analyzed by gas chromatograph (GC).After three days of data collection, the average AT, SR, ET and pH values were, respectively, 18oC, 2583kJm-2, 23oC and 8.2. Average values for GHG emission levels (CH4, CO2 and N2O) were 79.01; 100.65 and 0.0 mg m-2 h-1, respectively. GHG emission levels were divided into light periods (morning, afternoon and evening)in order to verify the periods with the highest GHG emissions.The highest CH4 emission levels were measured between morning and early afternoon. The maximum CO2 emissions were observed from evening to early morning. N2O emissions were constant and values were close to the ones found in the atmosphere, which shows the emission of N2O by facultative ponds does not contribute to greenhouse gases emissions.The results enabled us to characterize and quantify GHG emission levels per Facultative Pond on Wastewater Treatment Plant. Acknowledgment to FAPESP and SABESP, Brazil.

  20. Wetland treatment of oil and gas well wastewaters. Quarterly technical report, November 25, 1992--February 24, 1993

    SciTech Connect

    Kadlec, R.H.; Srinivasan, K.R.

    1993-04-02

    During the first quarter of the above contract, all the elements of Task 1 were completed. The first quarterly report presented an overview of a wetland and its increasing use in industrial wastewater treatment. An idealized, reaction engineering description of wetlands was presented to demonstrate how the various processes that occur in a wetland can be modeled. Previous work on the use of wetlands to remove BOD, TSS, Phosphorus and Nitrogen was reviewed. Recent literature on the application of wetland technology to the treatment of petroleum-related wastewater was critically evaluated and an outline of the research plans for the first year was delineated. Further, our literature search (nominally completed under Task 1) unearthed more recent studies (some unpublished) and a summary was included in the second quarterly report. In the second quarterly report, results of our efforts on the construction of a laboratory-type wetland were also reported. Initial studies on the use of wetland amendments such as modified-clays and algae cells were presented and discussed. Adsorption of heavy metal ions, Cu{sup 2+} and Cr(VI) onto soils drawn from the laboratory-type wetland built as a part of this contract has been undertaken and these results are presented and discussed in this quarterly report. A number of studies on the design and preparation of modified-clays for the adsorption of Cr(VI) and {beta}-naphthoic acid (NA) has been carried out during this quarter and these are also described and discussed in this report. The choice of {beta}-naphthoic acid (NA) as an ionogenic organic compound was made on the basis of a recent personal communication to the Project Director that NA is a major contaminant in many oil and gas well wastewaters.

  1. Identifying sensitive sources and key control handles for the reduction of greenhouse gas emissions from wastewater treatment.

    PubMed

    Sweetapple, Christine; Fu, Guangtao; Butler, David

    2014-10-01

    This research investigates the effects of adjusting control handle values on greenhouse gas emissions from wastewater treatment, and reveals critical control handles and sensitive emission sources for control through the combined use of local and global sensitivity analysis methods. The direction of change in emissions, effluent quality and operational cost resulting from variation of control handles individually is determined using one-factor-at-a-time sensitivity analysis, and corresponding trade-offs are identified. The contribution of each control handle to variance in model outputs, taking into account the effects of interactions, is then explored using a variance-based sensitivity analysis method, i.e., Sobol's method, and significant second order interactions are discovered. This knowledge will assist future control strategy development and aid an efficient design and optimisation process, as it provides a better understanding of the effects of control handles on key performance indicators and identifies those for which dynamic control has the greatest potential benefits. Sources with the greatest variance in emissions, and therefore the greatest need to monitor, are also identified. It is found that variance in total emissions is predominantly due to changes in direct N2O emissions and selection of suitable values for wastage flow rate and aeration intensity in the final activated sludge reactor is of key importance. To improve effluent quality, costs and/or emissions, it is necessary to consider the effects of adjusting multiple control handles simultaneously and determine the optimum trade-off.

  2. Greenhouse gas emissions from the treatment of household plastic containers and packaging: replacement with biomass-based materials.

    PubMed

    Yano, Junya; Hirai, Yasuhiro; Sakai, Shin-ichi; Tsubota, Jun

    2014-04-01

    The purpose of this study was to quantify the life-cycle greenhouse gas (GHG) emissions reduction that could be achieved by replacement of fossil-derived materials with biodegradable, biomass-based materials for household plastic containers and packaging, considering a variety of their treatment options. The biomass-based materials were 100% polylactide or a combination of polybutylene succinate adipate and polylactide. A scenario analysis was conducted considering alternative recycling methods. Five scenarios were considered: two for existing fossil-derived materials (the current approach in Japan) and the three for biomass-based materials. Production and waste disposal of 1 m(3) of plastic containers and packaging from households was defined as the functional unit. The results showed that replacement of fossil-derived materials with biomass-based materials could reduce life-cycle GHG emissions by 14-20%. Source separation and recycling should be promoted. When the separate collection ratio reached 100%, replacement with biomass-based materials could potentially reduce GHG emissions by 31.9%. Food containers are a priority for replacement, because they alone could reduce GHG emissions by 10%. A recycling system for biomass-based plastics must be carefully designed, considering aspects such as the transition period from fossil-derived plastics to biomass-based plastics.

  3. Identifying sensitive sources and key control handles for the reduction of greenhouse gas emissions from wastewater treatment.

    PubMed

    Sweetapple, Christine; Fu, Guangtao; Butler, David

    2014-10-01

    This research investigates the effects of adjusting control handle values on greenhouse gas emissions from wastewater treatment, and reveals critical control handles and sensitive emission sources for control through the combined use of local and global sensitivity analysis methods. The direction of change in emissions, effluent quality and operational cost resulting from variation of control handles individually is determined using one-factor-at-a-time sensitivity analysis, and corresponding trade-offs are identified. The contribution of each control handle to variance in model outputs, taking into account the effects of interactions, is then explored using a variance-based sensitivity analysis method, i.e., Sobol's method, and significant second order interactions are discovered. This knowledge will assist future control strategy development and aid an efficient design and optimisation process, as it provides a better understanding of the effects of control handles on key performance indicators and identifies those for which dynamic control has the greatest potential benefits. Sources with the greatest variance in emissions, and therefore the greatest need to monitor, are also identified. It is found that variance in total emissions is predominantly due to changes in direct N2O emissions and selection of suitable values for wastage flow rate and aeration intensity in the final activated sludge reactor is of key importance. To improve effluent quality, costs and/or emissions, it is necessary to consider the effects of adjusting multiple control handles simultaneously and determine the optimum trade-off. PMID:24960125

  4. Field emission from α-Fe2O3 nanoflakes: Effect of vacuum pressure, gas adsorption and in-situ thermal treatment

    NASA Astrophysics Data System (ADS)

    Wu, J. Q.; Deng, S. Z.; Xu, N. S.; Chen, Jun

    2014-02-01

    The effects of vacuum pressure and gas adsorption on field emission current of α-Fe2O3 nanoflakes were studied. It was found that field emission current of α-Fe2O3 nanoflakes decreased with increasing pressure. The field emission current decreased when N2 or O2 was introduced into chamber, while no obvious change was observed for H2 gas. An in-situ thermal treatment was carried out to eradicate the effect of absorbed gas. After the in-situ thermal treatment, the field emission current density was largely enhanced from 60 to 500 μA/cm2 under applied electrical field of 10 MV/m and the turn on field (Eturn-on) decreased from 7.6 to 5.2 MV/m. The lowered turn-on field was attributed to the decrease of surface work function induced by surface gas desorption and reduction of α-Fe2O3 nanoflakes. Moreover, the improvement of field emission performance can be retained in high vacuum condition, which indicates the in-situ thermal treatment is an efficient method to improve field emission properties of α-Fe2O3 nanoflakes.

  5. Laboratory Optimization Tests of Technetium Decontamination of Hanford Waste Treatment Plant Direct Feed Low Activity Waste Melter Off-Gas Condensate Simulant

    SciTech Connect

    Taylor-Pashow, K.; McCabe, D.

    2015-12-23

    The Hanford Waste Treatment and Immobilization Plant (WTP) Low Activity Waste (LAW) vitrification facility will generate an aqueous condensate recycle stream (LAW Off-Gas Condensate) from the off-gas system. The baseline plan for disposition of this stream is to send it to the WTP Pretreatment Facility, where it will be blended with LAW, concentrated by evaporation and recycled to the LAW vitrification facility. Alternate disposition of this stream would eliminate recycling of problematic components, and would enable less integrated operation of the LAW melter and the Pretreatment Facilities. Eliminating this stream from recycling within WTP would also decrease the LAW vitrification mission duration and quantity of glass waste.

  6. Stack gas treatment

    DOEpatents

    Reeves, Adam A.

    1977-04-12

    Hot stack gases transfer contained heat to a gravity flow of pebbles treated with a catalyst, cooled stacked gases and a sulfuric acid mist is withdrawn from the unit, and heat picked up by the pebbles is transferred to air for combustion or other process. The sulfuric acid (or sulfur, depending on the catalyst) is withdrawn in a recovery unit.

  7. Treatment

    MedlinePlus

    ... Prevention Treatment 2003 U.S. Outbreak African Rodent Importation Ban For Clinicians Clinical Recognition Specimen Collection Treatment Smallpox ... Examining Animals with Suspected Monkeypox African Rodent Importation Ban Resources Related Links Poxvirus Molluscum Contagiosum Orf Virus ( ...

  8. Application of the carbon dioxide-barium hydroxide hydrate gas-solid reaction for the treatment of dilute carbon dioxide-bearing gas streams

    SciTech Connect

    Haag, G.L.

    1983-09-01

    The removal of trace components from gas streams via irreversible gas-solid reactions in an area of interest to the chemical engineering profession. This research effort addresses the use of fixed beds of Ba(OH)/sub 2/ hydrate flakes for the removal of an acid gas, CO/sub 2/, from air that contains approx. 330 ppM/sub v/ CO/sub 2/. Areas of investigation encompassed: (1) an extensive literature review of Ba(OH)/sub 2/ hydrate chemistry, (2) microscale studies on 0.150-g samples to develop a better understanding of the reaction, (3) process studies at the macroscale level with 10.2-cm-ID fixed-bed reactors, and (4) the development of a model for predicting fixed-bed performance. Experimental studies indicated fixed beds of commercial Ba(OH)/sub 2/.8H/sub 2/O flakes at ambient temperatures to be capable of high CO/sub 2/-removal efficiencies (effluent concentrations <100 ppB), high reactant utilization (>99%), and an acceptable pressure drop (1.8 kPa/m at a superficial gas velocity of 13 cm/s). Ba(OH)/sub 2/.8H/sub 2/O was determined to be more reactive toward CO/sub 2/ than either Ba(OH)/sub 2/.3H/sub 2/O or Ba(OH)/sub 2/.1H/sub 2/O. A key variable in the development of this fixed-bed process was relative humidity. Operation at conditions with effluent relative humidities >60% resulted in significant recrystallization and restructuring of the flake and subsequent pressure-drop problems.

  9. Large-Scale Testing of Effects of Anti-Foam Agent on Gas Holdup in Process Vessels in the Hanford Waste Treatment Plant

    SciTech Connect

    Mahoney, L.A.; Alzheimer, J.M.; Arm, S.T.; Guzman-Leong, C.E.; Jagoda, L.K.; Stewart, C.W.; Wells, B.E.; Yokuda, S.T.

    2008-07-01

    The Hanford Waste Treatment and Immobilization Plant (WTP) will vitrify the radioactive wastes stored in underground tanks. These wastes generate and retain hydrogen and other flammable gases that create safety concerns for the vitrification process tanks in the WTP. An anti-foam agent (AFA) will be added to the WTP process streams. Previous testing in a bubble column and a small-scale impeller-mixed vessel indicated that gas holdup in a high-level waste chemical simulant with AFA was as much as 10 times higher than in clay simulant without AFA. This raised a concern that major modifications to the WTP design or qualification of an alternative AFA might be required to satisfy plant safety criteria. However, because the mixing and gas generation mechanisms in the small-scale tests differed from those expected in WTP process vessels, additional tests were performed in a large-scale prototypic mixing system with in situ gas generation. This paper presents the results of this test program. The tests were conducted at Pacific Northwest National Laboratory in a 1/4-scale model of the lag storage process vessel using pulse jet mixers and air spargers. Holdup and release of gas bubbles generated by hydrogen peroxide decomposition were evaluated in waste simulants containing an AFA over a range of Bingham yield stresses and gas generation rates. Results from the 1/4-scale test stand showed that, contrary to the small-scale impeller-mixed tests, holdup in the chemical waste simulant with AFA was not so greatly increased compared to gas holdup in clay without AFA. The test stand, simulants, scaling and data-analysis methods, and results are described in relation to previous tests and anticipated WTP operating conditions. (authors)

  10. Large-Scale Testing of Effects of Anti-Foam Agent on Gas Holdup in Process Vessels in the Hanford Waste Treatment Plant - 8280

    SciTech Connect

    Mahoney, Lenna A.; Alzheimer, James M.; Arm, Stuart T.; Guzman-Leong, Consuelo E.; Jagoda, Lynette K.; Stewart, Charles W.; Wells, Beric E.; Yokuda, Satoru T.

    2008-06-03

    The Hanford Waste Treatment Plant (WTP) will vitrify the radioactive wastes stored in underground tanks. These wastes generate and retain hydrogen and other flammable gases that create safety concerns for the vitrification process tanks in the WTP. An anti-foam agent (AFA) will be added to the WTP process streams. Prior testing in a bubble column and a small-scale impeller-mixed vessel indicated that gas holdup in a high-level waste chemical simulant with AFA was up to 10 times that in clay simulant without AFA. This raised a concern that major modifications to the WTP design or qualification of an alternative AFA might be required to satisfy plant safety criteria. However, because the mixing and gas generation mechanisms in the small-scale tests differed from those expected in WTP process vessels, additional tests were performed in a large-scale prototypic mixing system with in situ gas generation. This paper presents the results of this test program. The tests were conducted at Pacific Northwest National Laboratory in a ¼-scale model of the lag storage process vessel using pulse jet mixers and air spargers. Holdup and release of gas bubbles generated by hydrogen peroxide decomposition were evaluated in waste simulants containing an AFA over a range of Bingham yield stresses and gas gen geration rates. Results from the ¼-scale test stand showed that, contrary to the small-scale impeller-mixed tests, gas holdup in clay without AFA is comparable to that in the chemical waste simulant with AFA. The test stand, simulants, scaling and data-analysis methods, and results are described in relation to previous tests and anticipated WTP operating conditions.

  11. Surface acoustic wave gas sensor for nitrogen dioxide using phthalocyanines as chemical interfaces. Effects of nitric oxide, halogen gases, and prolonged heat treatment

    SciTech Connect

    Nieuwenhuizen, M.S.; Nederlof, A.J.

    1988-02-01

    The effect of CO, NO, and O/sub 2/ on the response of a SAW (surface acoustic wave) chemosensor for NO/sub 2/ has been studied. A description is given of the measuring equipment existing of a mass flow controlled automatic gas dilution system. Copper and iron phthalocyanine were used as the chemical interface. Simultaneously, the influence of ambient atmospheres (N/sub 2/ and O/sub 2/) was investigated. Predictions from ultraviolet-visible experiments in solution do not hold for gaseous environments. Also the effect of electronegative gases like the halogens was studied. Response up to 40 times the NO/sub 2/ response was measured. Prolonged heat treatment affects the sensitivity for NO/sub 2/ negatively as well as the response time. This asks for a more stable chemical interface. All results are discussed in terms of general performance criteria for gas sensors such as selectivity, sensitivity, response time, reversibility, and stability.

  12. Apparatus Circulates Sterilizing Gas

    NASA Technical Reports Server (NTRS)

    Cross, John H.; Schwarz, Ray P.

    1991-01-01

    Apparatus circulates sterilizing gas containing ethylene oxide and chlorofluorocarbon through laboratory or medical equipment. Confines sterilizing gas, circulating it only through parts to be treated. Consists of two units. One delivers ethylene oxide/chlorofluorocarbon gas mixture and removes gas after treatment. Other warms, humidifies, and circulates gas through equipment to be treated. Process provides reliable sterilization with negligible residual toxicity from ethylene oxide. Particularly suitable for sterilization of interiors of bioreactors, heart/lung machines, dialyzers, or other equipment including complicated tubing.

  13. Neural network analysis on the effect of heat fluxes on greenhouse gas emissions from anaerobic swine waste treatment lagoon

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this study, we examined the various meteorological factors (i.e., air temperatures, solar radiation, and heat fluxes) that potentially affect greenhouse gas (GHG) emissions from swine waste lagoon. GHG concentrations (methane, carbon dioxide, and nitrous oxide) were monitored using a photoacous...

  14. TECHNICAL ASSESSMENT OF FUEL CELL OPERATION ON ANAEROBIC DIGESTER GAS AT THE YONKERS, NY, WASTEWATER TREATMENT PLANT

    EPA Science Inventory

    The paper summarizes the results of a 2-year field test to assess the performance of a specially modified commercial phosphoric acid 200 kW fuel cell power plant to recover energy from anaerobic digester gas (ADG) which has been cleansed of contaminants (sulfur and halide compoun...

  15. Differential Treatment of Pregnancy in Employment: The Impact of "General Electric Co. v. Gilbert" and "Nashville Gas Co. v. Satty."

    ERIC Educational Resources Information Center

    Taylor, Ellen T.

    1978-01-01

    After discussing the facts and reasoning of the two cases (General Electric Co. vs Gilbert and Nashville Gas Co. vs Satty), the author argues that the decisions are largely the product of pregnancy stereotypes and that the Court's reasoning is flawed and should not be applied outside the context of pregnancy. Journal availability: see EA 511 481.…

  16. Novel pre-treatment of zeolite materials for the removal of sodium ions: potential materials for coal seam gas co-produced wastewater.

    PubMed

    Santiago, Oscar; Walsh, Kerry; Kele, Ben; Gardner, Edward; Chapman, James

    2016-01-01

    Coal seam gas (CSG) is the extraction of methane gas that is desorbed from the coal seam and brought to the surface using a dewatering and depressurisation process within the saturated coalbed. The extracted water is often referred to as co-produced CSG water. In this study, co-produced water from the coal seam of the Bowen Basin (QLD, Australia) was characterised by high concentration levels of Na(+) (1156 mg/L), low concentrations of Ca(2+) (28.3 mg/L) and Mg(2+) (5.6 mg/L), high levels of salinity, which are expected to cause various environmental problems if released to land or waters. The potential treatment of co-produced water using locally sourced natural ion exchange (zeolite) material was assessed. The zeolite material was characterized for elemental composition and crystal structure. Natural, untreated zeolite demonstrated a capacity to adsorb Na(+) ions of 16.16 mEq/100 g, while a treated zeolite using NH4 (+) using a 1.0 M ammonium acetate (NH4C2H3O2) solution demonstrated an improved 136 % Na(+) capacity value of 38.28 mEq/100 g after 720 min of adsorption time. The theoretical exchange capacity of the natural zeolite was found to be 154 mEq/100 g. Reaction kinetics and diffusion models were used to determine the kinetic and diffusion parameters. Treated zeolite using a NH4 (+) pre-treatment represents an effective treatment to reduce Na(+) concentration in coal seam gas co-produced waters, supported by the measured and modelled kinetic rates and capacity. PMID:27247868

  17. Scale-Up Information for Gas-Phase Ammonia Treatment of Uranium in the Vadose Zone at the Hanford Site Central Plateau

    SciTech Connect

    Truex, Michael J.; Szecsody, James E.; Zhong, Lirong; Thomle, Jonathan N.; Johnson, Timothy C.

    2014-09-01

    Uranium is present in the vadose zone at the Hanford Central Plateau and is of concern for protection of groundwater. The Deep Vadose Zone Treatability Test Plan for the Hanford Central Plateau identified gas-phase treatment and geochemical manipulation as potentially effective treatment approaches for uranium and technetium in the Hanford Central Plateau vadose zone. Based on laboratory evaluation, use of ammonia vapor was selected as the most promising uranium treatment candidate for further development and field testing. While laboratory tests have shown that ammonia treatment effectively reduces the mobility of uranium, additional information is needed to enable deployment of this technology for remediation. Of importance for field applications are aspects of the technology associated with effective distribution of ammonia to a targeted treatment zone, understanding the fate of injected ammonia and its impact on subsurface conditions, and identifying effective monitoring approaches. In addition, information is needed to select equipment and operational parameters for a field design. As part of development efforts for the ammonia technology for remediation of vadose zone uranium contamination, field scale-up issues were identified and have been addressed through a series of laboratory and modeling efforts. This report presents a conceptual description for field application of the ammonia treatment process, engineering calculations to support treatment design, ammonia transport information, field application monitoring approaches, and a discussion of processes affecting the fate of ammonia in the subsurface. The report compiles this information from previous publications and from recent research and development activities. The intent of this report is to provide technical information about these scale-up elements to support the design and operation of a field test for the ammonia treatment technology.

  18. A statistical analysis of the effects of urease pre-treatment on the measurement of the urinary metabolome by gas chromatography–mass spectrometry

    SciTech Connect

    Webb-Robertson, Bobbie-Jo; Kim, Young -Mo; Zink, Erika M.; Hallaian, Katherine A.; Zhang, Qibin; Madupu, Ramana; Waters, Katrina M.; Metz, Thomas O.

    2014-02-27

    Urease pre-treatment of urine has been utilized since the early 1960s to remove high levels of urea from samples prior to further processing and analysis by gas chromatography-mass spectrometry (GC-MS). Aside from the obvious depletion or elimination of urea, the effect, if any, of urease pre-treatment on the urinary metabolome has not been studied in detail. Here, we report the results of three separate but related experiments that were designed to assess possible indirect effects of urease pre-treatment on the urinary metabolome as measured by GC-MS. In total, 235 GC-MS analyses were performed and over 106 identified and 200 unidentified metabolites were quantified across the three experiments. The results showed that data from urease pre-treated samples 1) had the same or lower coefficients of variance among reproducibly detected metabolites, 2) more accurately reflected quantitative differences and the expected ratios among different urine volumes, and 3) increased the number of metabolite identifications. Altogether, we observed no negative consequences of urease pre-treatment. In contrast, urease pretreatment enhanced the ability to distinguish between volume-based and biological sample types compared to no treatment. Taken together, these results show that urease pretreatment of urine offers multiple beneficial effects that outweigh any artifacts that may be introduced to the data in urinary metabolomics analyses.

  19. A statistical analysis of the effects of urease pre-treatment on the measurement of the urinary metabolome by gas chromatography–mass spectrometry

    DOE PAGESBeta

    Webb-Robertson, Bobbie-Jo; Kim, Young -Mo; Zink, Erika M.; Hallaian, Katherine A.; Zhang, Qibin; Madupu, Ramana; Waters, Katrina M.; Metz, Thomas O.

    2014-02-27

    Urease pre-treatment of urine has been utilized since the early 1960s to remove high levels of urea from samples prior to further processing and analysis by gas chromatography-mass spectrometry (GC-MS). Aside from the obvious depletion or elimination of urea, the effect, if any, of urease pre-treatment on the urinary metabolome has not been studied in detail. Here, we report the results of three separate but related experiments that were designed to assess possible indirect effects of urease pre-treatment on the urinary metabolome as measured by GC-MS. In total, 235 GC-MS analyses were performed and over 106 identified and 200 unidentifiedmore » metabolites were quantified across the three experiments. The results showed that data from urease pre-treated samples 1) had the same or lower coefficients of variance among reproducibly detected metabolites, 2) more accurately reflected quantitative differences and the expected ratios among different urine volumes, and 3) increased the number of metabolite identifications. Altogether, we observed no negative consequences of urease pre-treatment. In contrast, urease pretreatment enhanced the ability to distinguish between volume-based and biological sample types compared to no treatment. Taken together, these results show that urease pretreatment of urine offers multiple beneficial effects that outweigh any artifacts that may be introduced to the data in urinary metabolomics analyses.« less

  20. Economical assessment of the design, construction and operation of open-bed biofilters for waste gas treatment.

    PubMed

    Prado, O J; Gabriel, D; Lafuente, J

    2009-06-01

    A protocol was developed with the purpose of assessing the main costs implied in the set-up, operation and maintenance of a waste gas-treating conventional biofilter. The main operating parameters considered in the protocol were the empty bed residence time and the gas flow rate. A wide variety of investment and operating costs were considered. In order to check its reliability, the protocol was applied to a number of scenarios, with biofilter volumes ranging from 8.3 to 4000 m(3). Results show that total annualized costs were between 20,000 and 220,000 euro/year and directly dependent, among other factors, on the size of the system. Total investment and operating costs for average-size compost biofilters were around 60,000 euro and 20,000 euro/year, respectively, which are concordant with actual costs. Also, a sensitivity analysis was performed in order to assess the relative influence of a series of selected costs. Results prove that operating costs are those that influence the total annual costs to a higher extent. Also, packing material replacement costs contribute significantly to the total yearly costs in biofilters with a volume higher than 800 m(3). Among operating costs, the electricity consumption is the main influencing factor in biofilters with a gas flow rate above 50,000 m(3)/h, while labor costs are critical at lower gas flow rates. In addition, the use of a variety of packing materials commonly employed in biofiltration was assessed. According to the results obtained, special attention should be paid to the packing material selected, as it is the main parameter influencing the medium replacement costs, and one of the main factors affecting investment costs.

  1. Field measurement of greenhouse gas emission rates and development of emission factors for wastewater treatment. Final report, September 1994-March 1997

    SciTech Connect

    Eklund, B.; LaCosse, J.

    1997-09-01

    The report gives results of field testing to develop more reliable greenhouse gas (GHG) emission estimates for Wastewater treatment (WWT) lagoons. Field tests of emissions were conducted for WWT lagoons that use anaerobic processes to treat large volumes of wastewater with large biological oxygen demand (BOD) loadings. Air emissions and wastewater were measured at anaerobic lagoons at three meat processing plants and two publicly owned treatment works. The overall emission rates of CH4, carbon dioxide, carbon monoxide, nitrous oxide, ammonia (NH3), and chlorofluorocarbons were measured from each source using an open-path monitoring approach. The emitted compounds were identified and quantified by Fourier-Transform Infrared spectroscopy. Emission factors were developed for CH4 and NH3 as a function of the plant production rate, wastewater parameters (e.g., influent BOD and chemical oxygen demand (COD) loadings), and WWT system performance (e.g., BOD and COD removal rates).

  2. Effectiveness of sanitizers, dry heat, hot water, and gas catalytic infrared heat treatments to inactivate Salmonella on almonds.

    PubMed

    Bari, Md Latiful; Nei, Daisuke; Sotome, Itaru; Nishina, Ikuo; Isobe, Seiichi; Kawamoto, Shinnichi

    2009-10-01

    The majority of almond-related foodborne outbreaks have been associated with Salmonella. Therefore, it is necessary to find an effective method to inactivate these organisms on raw almond prior to market distribution. This study was conducted to assess the effectiveness of sanitizers (strong or mild electrolyzed water, ozonated water, and distilled water), dry heat treatment, and hot water treatments followed by catalytic infrared (IR) heat treatment to inactivate Salmonella populations on raw almond. Raw almonds inoculated with four-strain cocktails of Salmonella were treated either by soaking in different chemical sanitizers or with dry heat and/or hot water for various periods of time followed by catalytic IR heat treatment for 70 seconds. The treated seeds were then assessed for the efficacy of the treatment in reducing populations of the pathogens. After inoculation and air-drying, 5.73 +/- 0.12 log colony-forming units (CFU)/g Salmonella were detected in nonselective medium. Sanitizer treatment alone did not show significant reduction in the Salmonella population, but in combination with IR drying it reduced the population to 3.0 log CFU/g. Dry heating at 60 degrees C for 4 days followed by IR drying for 70 seconds reduced the Salmonella population an additional 1.0 log CFU/g. Hot water treatments at 85 degrees C for 40 seconds followed by IR drying for 70 seconds reduced pathogens to an undetectable level by direct plating, but not by enrichment. PMID:19622034

  3. Utilization of Common Automotive Three-Way NO{sub x} Reduction Catalyst for Managing Off- Gas from Thermal Treatment of High-Nitrate Waste - 13094

    SciTech Connect

    Foster, Adam L.; Ki Song, P.E.

    2013-07-01

    Studsvik's Thermal Organic Reduction (THOR) steam reforming process has been tested and proven to effectively treat radioactive and hazardous wastes streams with high nitrate contents to produce dry, stable mineral products, while providing high conversion (>98%) of nitrates and nitrites directly to nitrogen gas. However, increased NO{sub x} reduction may be desired for some waste streams under certain regulatory frameworks. In order to enhance the NO{sub x} reduction performance of the THOR process, a common Three-Way catalytic NO{sub x} reduction unit was installed in the process gas piping of a recently completed Engineering Scale Technology Demonstration (ESTD). The catalytic DeNO{sub x} unit was located downstream of the main THOR process vessel, and it was designed to catalyze the reduction of residual NO{sub x} to nitrogen gas via the oxidation of the hydrogen, carbon monoxide, and volatile organic compounds that are inherent to the THOR process gas. There was no need for auxiliary injection of a reducing gas, such as ammonia. The unit consisted of four monolith type catalyst sections positioned in series with a gas mixing section located between each catalyst section. The process gas was monitored for NO{sub x} concentration upstream and downstream of the catalytic DeNO{sub x} unit. Conversion efficiencies ranged from 91% to 97% across the catalytic unit, depending on the composition of the inlet gas. Higher concentrations of hydrogen and carbon monoxide in the THOR process gas increased the NO{sub x} reduction capability of the catalytic DeNO{sub x} unit. The NO{sub x} destruction performance of THOR process in combination with the Three-Way catalytic unit resulted in overall system NO{sub x} reduction efficiencies of greater than 99.9% with an average NO{sub x} reduction efficiency of 99.94% for the entire demonstration program. This allowed the NO{sub x} concentration in the ESTD exhaust gas to be maintained at less than 40 parts per million (ppm), dry

  4. Development of Combined Dry Heat and Chlorine Dioxide Gas Treatment with Mechanical Mixing for Inactivation of Salmonella enterica Serovar Montevideo on Mung Bean Seeds.

    PubMed

    Annous, Bassam A; Burke, Angela

    2015-05-01

    Foodborne outbreaks have been associated with the consumption of fresh sprouted beans. The sprouting conditions of mung bean seeds provide optimal conditions of temperature and relative humidity for any potential pathogenic contaminant on the seeds to grow. The lack of a kill step postsprouting is a major safety concern. Thus, the use of a kill step on the seeds prior to a sprouting step would enhance the safety of fresh sprouts. The objective of this work was to evaluate the effectiveness of the combined thermal and chlorine dioxide gas (3.5 mg/liter of air) treatment with mechanical mixing (tumbling) to eliminate Salmonella on artificially inoculated mung bean seeds. Although no viable Salmonella was recovered from seeds treated in hot water at 60°C for 2 h, these treated seeds failed to germinate. Dry heat treatments (55, 60, or 70°C) for up to 8 h reduced Salmonella populations in excess of 3 log CFU/g. The use of tumbling, while treating the seeds, resulted in up to 1.6 log CFU/g reduction in Salmonella populations compared with no tumbling. Dry heat treatment at 65°C for 18 h with tumbling resulted in a complete inactivation of Salmonella populations on inoculated seeds with low inoculum levels (2.83 log CFU/g) as compared with high inoculum levels (4.75 log CFU/g). The increased reductions in pathogenic populations on the seeds with the use of tumbling could be attributed to increased uniformity of heat transfer and exposure to chlorine dioxide gas. All treated seeds were capable of germinating, as well as the nontreated controls. These results suggest that this combined treatment would be a viable process for enhancing the safety of fresh sprouts. PMID:25951379

  5. Discharges of produced waters from oil and gas extraction via wastewater treatment plants are sources of disinfection by-products to receiving streams.

    PubMed

    Hladik, Michelle L; Focazio, Michael J; Engle, Mark

    2014-01-01

    Fluids co-produced with oil and gas production (produced waters) are often brines that contain elevated concentrations of bromide. Bromide is an important precursor of several toxic disinfection by-products (DBPs) and the treatment of produced water may lead to more brominated DBPs. To determine if wastewater treatment plants that accept produced waters discharge greater amounts of brominated DBPs, water samples were collected in Pennsylvania from four sites along a large river including an upstream site, a site below a publicly owned wastewater treatment plant (POTW) outfall (does not accept produced water), a site below an oil and gas commercial wastewater treatment plant (CWT) outfall, and downstream of the POTW and CWT. Of 29 DBPs analyzed, the site at the POTW outfall had the highest number detected (six) ranging in concentration from 0.01 to 0.09 μg L(-1) with a similar mixture of DBPs that have been detected at POTW outfalls elsewhere in the United States. The DBP profile at the CWT outfall was much different, although only two DBPs, dibromochloronitromethane (DBCNM) and chloroform, were detected, DBCNM was found at relatively high concentrations (up to 8.5 μg L(-1)). The water at the CWT outfall also had a mixture of inorganic and organic precursors including elevated concentrations of bromide (75 mg L(-1)) and other organic DBP precursors (phenol at 15 μg L(-1)). To corroborate these DBP results, samples were collected in Pennsylvania from additional POTW and CWT outfalls that accept produced waters. The additional CWT also had high concentrations of DBCNM (3.1 μg L(-1)) while the POTWs that accept produced waters had elevated numbers (up to 15) and concentrations of DBPs, especially brominated and iodinated THMs (up to 12 μg L(-1) total THM concentration). Therefore, produced water brines that have been disinfected are potential sources of DBPs along with DBP precursors to streams wherever these wastewaters are discharged.

  6. Discharges of produced waters from oil and gas extraction via wastewater treatment plants are sources of disinfection by-products to receiving streams

    USGS Publications Warehouse

    Hladik, Michelle L.; Focazio, Michael J.; Engle, Mark

    2014-01-01

    Fluids co-produced with oil and gas production (produced waters) are often brines that contain elevated concentrations of bromide. Bromide is an important precursor of several toxic disinfection by-products (DBPs) and the treatment of produced water may lead to more brominated DBPs. To determine if wastewater treatment plants that accept produced waters discharge greater amounts of brominated DBPs, water samples were collected in Pennsylvania from four sites along a large river including an upstream site, a site below a publicly owned wastewater treatment plant (POTW) outfall (does not accept produced water), a site below an oil and gas commercial wastewater treatment plant (CWT) outfall, and downstream of the POTW and CWT. Of 29 DBPs analyzed, the site at the POTW outfall had the highest number detected (six) ranging in concentration from 0.01 to 0.09 μg L− 1 with a similar mixture of DBPs that have been detected at POTW outfalls elsewhere in the United States. The DBP profile at the CWT outfall was much different, although only two DBPs, dibromochloronitromethane (DBCNM) and chloroform, were detected, DBCNM was found at relatively high concentrations (up to 8.5 μg L− 1). The water at the CWT outfall also had a mixture of inorganic and organic precursors including elevated concentrations of bromide (75 mg L− 1) and other organic DBP precursors (phenol at 15 μg L− 1). To corroborate these DBP results, samples were collected in Pennsylvania from additional POTW and CWT outfalls that accept produced waters. The additional CWT also had high concentrations of DBCNM (3.1 μg L− 1) while the POTWs that accept produced waters had elevated numbers (up to 15) and concentrations of DBPs, especially brominated and iodinated THMs (up to 12 μg L− 1 total THM concentration). Therefore, produced water brines that have been disinfected are potential sources of DBPs along with DBP precursors to streams wherever these wastewaters are discharged.

  7. Development of Combined Dry Heat and Chlorine Dioxide Gas Treatment with Mechanical Mixing for Inactivation of Salmonella enterica Serovar Montevideo on Mung Bean Seeds.

    PubMed

    Annous, Bassam A; Burke, Angela

    2015-05-01

    Foodborne outbreaks have been associated with the consumption of fresh sprouted beans. The sprouting conditions of mung bean seeds provide optimal conditions of temperature and relative humidity for any potential pathogenic contaminant on the seeds to grow. The lack of a kill step postsprouting is a major safety concern. Thus, the use of a kill step on the seeds prior to a sprouting step would enhance the safety of fresh sprouts. The objective of this work was to evaluate the effectiveness of the combined thermal and chlorine dioxide gas (3.5 mg/liter of air) treatment with mechanical mixing (tumbling) to eliminate Salmonella on artificially inoculated mung bean seeds. Although no viable Salmonella was recovered from seeds treated in hot water at 60°C for 2 h, these treated seeds failed to germinate. Dry heat treatments (55, 60, or 70°C) for up to 8 h reduced Salmonella populations in excess of 3 log CFU/g. The use of tumbling, while treating the seeds, resulted in up to 1.6 log CFU/g reduction in Salmonella populations compared with no tumbling. Dry heat treatment at 65°C for 18 h with tumbling resulted in a complete inactivation of Salmonella populations on inoculated seeds with low inoculum levels (2.83 log CFU/g) as compared with high inoculum levels (4.75 log CFU/g). The increased reductions in pathogenic populations on the seeds with the use of tumbling could be attributed to increased uniformity of heat transfer and exposure to chlorine dioxide gas. All treated seeds were capable of germinating, as well as the nontreated controls. These results suggest that this combined treatment would be a viable process for enhancing the safety of fresh sprouts.

  8. Effect of heat treatment on longitudinal gas and liquid permeability of circular and square-shaped native hardwood specimens

    NASA Astrophysics Data System (ADS)

    Taghiyari, Hamid Reza; Moradi Malek, Bahman

    2014-08-01

    Effects of heat-treatment on longitudinal permeability of circular and square wood specimens were studied here. Specimens were heated to 50, 75, 100, 125, 150, and 185 °C. Results showed that permeability increased at the lowest temperature due to shrinkage; then, it decreased due to irreversible hydrogen bonding and stiffness. The highest temperature increased permeability due to micro-cracks. The higher perimeter in the square specimens aggravated the effects of heat treatment.

  9. Analysis of gas exchange, stomatal behaviour and micronutrients uncovers dynamic response and adaptation of tomato plants to monochromatic light treatments.

    PubMed

    O'Carrigan, Andrew; Babla, Mohammad; Wang, Feifei; Liu, Xiaohui; Mak, Michelle; Thomas, Richard; Bellotti, Bill; Chen, Zhong-Hua

    2014-09-01

    Light spectrum affects the yield and quality of greenhouse tomato, especially over a prolonged period of monochromatic light treatments. Physiological and chemical analysis was employed to investigate the influence of light spectral (blue, green and red) changes on growth, photosynthesis, stomatal behaviour, leaf pigment, and micronutrient levels. We found that plants are less affected under blue light treatment, which was evident by the maintenance of higher A, gs, Tr, and stomatal parameters and significantly lower VPD and Tleaf as compared to those plants grown in green and red light treatments. Green and red light treatments led to significantly larger increase in the accumulation of Fe, B, Zn, and Cu than blue light. Moreover, guard cell length, width, and volume all showed highly significant positive correlations to gs, Tr and negative links to VPD. There was negative impact of monochromatic lights-induced accumulation of Mn, Cu, and Zn on photosynthesis, leaf pigments and plant growth. Furthermore, most of the light-induced significant changes of the physiological traits were partially recovered at the end of experiment. A high degree of morphological and physiological plasticity to blue, green and red light treatments suggested that tomato plants may have developed mechanisms to adapt to the light treatments. Thus, understanding the optimization of light spectrum for photosynthesis and growth is one of the key components for greenhouse tomato production.

  10. Co and Fe-catalysts supported on sepiolite: effects of preparation conditions on their catalytic behaviors in high temperature gas flow treatment of dye.

    PubMed

    Lin, Xiangfeng; Fang, Jian; Chen, Menglin; Huang, Zhi; Su, Chengyuan

    2016-08-01

    An efficient adsorbent/catalyst Co and Fe-catalysts loaded on sepiolite (Co-Fe/sepiolite) was successfully prepared for high temperature gas flow catalytic reaction by a simple impregnation method. The impact of preparation conditions (such as pH value of impregnation solution, impregnation time, calcination temperature, and time) on catalytic activity was studied. We found that the catalytic activity of Co-Fe/sepiolite was strongly influenced by all the investigated parameters. The regeneration efficiency (RE) was used to evaluate the catalytic activity. The RE is more noticeable at pH 5.0 of impregnation solution, impregnation time 18 h, calcination temperature 650 °C, and calcination time 3 h. This Co-Fe/sepiolite has great adsorption capacity in absorbing dye. It is used for an adsorbent to adsorb dye from wastewater solution under dynamic adsorption and saturated with dye, then regenerated with high temperature gas flow for adsorption/oxidation cycles. The Co-Fe/sepiolite acts as a catalyst to degrade the dye during regeneration under high temperature gas flow. Hence, the Co-Fe/sepiolite is not only an adsorbent but also a catalyst. The Co-Fe/sepiolite is more stable than sepiolite when applied in the treatment of plant's wastewater. The Co-Fe/sepiolite can be reused in adsorption-regeneration cycle. The results indicate the usability of the proposed combined process, dye adsorption on Co-Fe/sepiolite followed by the catalytic oxidation in high temperature gas flow. PMID:27102621

  11. Phase I: the pipeline-gas demonstration plant. Demonstration plant engineering and design. Volume 18. Plant Section 2700 - Waste Water Treatment

    SciTech Connect

    1981-05-01

    Contract No. EF-77-C-01-2542 between Conoco Inc. and the US Department of Energy provides for the design, construction, and operation of a demonstration plant capable of processing bituminous caking coals into clean pipeline quality gas. The project is currently in the design phase (Phase I). This phase is scheduled to be completed in June 1981. One of the major efforts of Phase I is the process and project engineering design of the Demonstration Plant. The design has been completed and is being reported in 24 volumes. This is Volume 18 which reports the design of Plant Section 2700 - Waste Water Treatment. The objective of the Waste Water Treatment system is to collect and treat all plant liquid effluent streams. The system is designed to permit recycle and reuse of the treated waste water. Plant Section 2700 is composed of primary, secondary, and tertiary waste water treatment methods plus an evaporation system which eliminates liquid discharge from the plant. The Waste Water Treatment Section is designed to produce 130 pounds per hour of sludge that is buried in a landfill on the plant site. The evaporated water is condensed and provides a portion of the make-up water to Plant Section 2400 - Cooling Water.

  12. Nontargeted evaluation of the fate of steroids during wastewater treatment by comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry.

    PubMed

    Kopperi, Matias; Parshintsev, Jevgeni; Ruiz-Jiménez, José; Riekkola, Marja-Liisa

    2016-09-01

    Emerging organic contaminants in wastewater are usually analyzed by targeted approaches, and especially estrogens have been the focus of environmental research due to their high hormonal activity. The selection of specific target compounds means, however, that most of the sample components, including transformation products and potential new contaminants, are neglected. In this study, the fate of steroidal compounds in wastewater treatment processes was evaluated by a nontargeted approach based on comprehensive two-dimensional gas chromatography-time-of-flight mass spectrometry. The potential of the nontargeted approach to generate comprehensive information about sample constituents was demonstrated with use of statistical tools. Transformation pathways of the tentatively identified compounds with steroidal four-ring structure were proposed. The purification efficiency of the wastewater treatment plants was studied, and the distribution of the compounds of interest in the suspended solids, effluent water, and sludge was measured. The results showed that, owing to strong adsorption of hydrophobic compounds onto the solid matter, the steroids were mostly bound to the suspended solids of the effluent water and the sewage sludge at the end of the treatment process. The most abundant steroid class was androstanes in the aqueous phase and cholestanes in the solid phase. 17β-estradiol was the most abundant estrogen in the aqueous phase, but it was only detected in the influent samples indicating efficient removal during the treatment process. In the sludge samples, however, high concentrations of an oxidation product of 17β-estradiol, estrone, were measured. PMID:27206750

  13. Atmospheric plasma jet array in parallel electric and gas flow fields for three-dimensional surface treatment

    NASA Astrophysics Data System (ADS)

    Cao, Z.; Walsh, J. L.; Kong, M. G.

    2009-01-01

    This letter reports on electrical and optical characteristics of a ten-channel atmospheric pressure glow discharge jet array in parallel electric and gas flow fields. Challenged with complex three-dimensional substrates including surgical tissue forceps and sloped plastic plate of up to 15°, the jet array is shown to achieve excellent jet-to-jet uniformity both in time and in space. Its spatial uniformity is four times better than a comparable single jet when both are used to treat a 15° sloped substrate. These benefits are likely from an effective self-adjustment mechanism among individual jets facilitated by individualized ballast and spatial redistribution of surface charges.

  14. Contribution of Liquid/Gas Mass-Transfer Limitations to Dissolved Methane Oversaturation in Anaerobic Treatment of Dilute Wastewater.

    PubMed

    Yeo, Hyeongu; An, Junyeong; Reid, Robertson; Rittmann, Bruce E; Lee, Hyung-Sool

    2015-09-01

    The mechanisms controlling the accumulation of dissolved methane in anaerobic membrane bioreactors (AnMBRs) treating a synthetic dilute wastewater (a glucose medium) were assessed experimentally and theoretically. The AnMBR was maintained at a temperature of 24-26 °C as the organic loading rate increased from 0.39 to 1.1 kg COD/m(3)-d. The measured concentration of dissolved methane was consistently 2.2- to 2.5-fold larger than the concentration of dissolved methane at thermodynamic equilibrium with the measured CH4 partial pressure, and the fraction of dissolved methane was as high as 76% of the total methane produced. The low gas production rate in the AnMBR significantly slowed the mass transport of dissolved methane to the gas phase. Although the production rate of total methane increased linearly with the COD loading rate, the concentration of dissolved methane only slightly increased with an increasing organic loading rate, because the mass-transfer rate increased by almost 5-fold as the COD loading increased from 0.39 to 1.1 kg COD/m(3)-d. Thus, slow mass transport kinetics exacerbated the situation in which dissolved methane accounted for a substantial fraction of the total methane generated from the AnMBR. PMID:26238158

  15. Effect of UV-ozone treatment on poly(dimethylsiloxane) membranes: surface characterization and gas separation performance.

    PubMed

    Fu, Ywu-Jang; Qui, Hsuan-zhi; Liao, Kuo-Sung; Lue, Shingjiang Jessie; Hu, Chien-Chieh; Lee, Kueir-Rarn; Lai, Juin-Yih

    2010-03-16

    A thin SiO(x) selective surface layer was formed on a series of cross-linked poly(dimethylsiloxane) (PDMS) membranes by exposure to ultraviolet light at room temperature in the presence of ozone. The conversion of the cross-linked polysiloxane to SiO(x) was monitored by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray (EDX) microanalysis, contact angle analysis, and atomic force microscopy (AFM). The conversion of the cross-linked polysiloxane to SiO(x) increased with UV-ozone exposure time and cross-linking agent content, and the surface possesses highest conversion. The formation of a SiO(x) layer increased surface roughness, but it decreased water contact angle. Gas permeation measurements on the UV-ozone exposure PDMS membranes documented interesting gas separation properties: the O(2) permeability of the cross-linked PDMS membrane before UV-ozone exposure was 777 barrer, and the O(2)/N(2) selectivity was 1.9; after UV-ozone exposure, the permeability decreased to 127 barrer while the selectivity increased to 5.4. The free volume depth profile of the SiO(x) layer was investigated by novel slow positron beam. The results show that free volume size increased with the depth, yet the degree of siloxane conversion to SiO(x) does not affect the amount of free volume.

  16. Contribution of Liquid/Gas Mass-Transfer Limitations to Dissolved Methane Oversaturation in Anaerobic Treatment of Dilute Wastewater.

    PubMed

    Yeo, Hyeongu; An, Junyeong; Reid, Robertson; Rittmann, Bruce E; Lee, Hyung-Sool

    2015-09-01

    The mechanisms controlling the accumulation of dissolved methane in anaerobic membrane bioreactors (AnMBRs) treating a synthetic dilute wastewater (a glucose medium) were assessed experimentally and theoretically. The AnMBR was maintained at a temperature of 24-26 °C as the organic loading rate increased from 0.39 to 1.1 kg COD/m(3)-d. The measured concentration of dissolved methane was consistently 2.2- to 2.5-fold larger than the concentration of dissolved methane at thermodynamic equilibrium with the measured CH4 partial pressure, and the fraction of dissolved methane was as high as 76% of the total methane produced. The low gas production rate in the AnMBR significantly slowed the mass transport of dissolved methane to the gas phase. Although the production rate of total methane increased linearly with the COD loading rate, the concentration of dissolved methane only slightly increased with an increasing organic loading rate, because the mass-transfer rate increased by almost 5-fold as the COD loading increased from 0.39 to 1.1 kg COD/m(3)-d. Thus, slow mass transport kinetics exacerbated the situation in which dissolved methane accounted for a substantial fraction of the total methane generated from the AnMBR.

  17. Characterization of oil and gas waste disposal practices and assessment of treatment costs. Yearly report, July 1, 1992--June 30, 1993

    SciTech Connect

    Bedient, P.B.

    1993-07-30

    The project consists of 3 tasks: (1) Developing a Production Environmental Database (PED) with the purpose of investigating the current industry waste storage and disposal practices by different regions, states and types of waste and investigating the environmental impacts associated with these practices; (2) Evaluating the suitability of available and developing technologies for treating produced water and identifying applicable unit process configurations; and (3) Evaluating the costs associated with various degrees of treatment achievable by different configurations. Records of wells drilled during the years 1986 through 1991 were compiled from industry reports. Overall, drilling has decreased from an average of 60,000 wells/yr for the period 1981 through 1985 to 20,000/yr during 1986 through 1991. A produced water database was developed from data and information provided by the various state and federal agencies. Currently, the database has information on the production of oil, gas and brines from 24 states. The data from the produced water database indicate that for the most part, Class II Injection seemed to be the common disposal method. Other methods included evaporation, surface disposal via NPDES permit, road spreading, hauling out-of-state, and annular disposal. A survey of oil and gas operators has been developed, reviewed and edited. The survey is divided-by topic into three sections. (1) drilling wastes; (2) associated wastes; and (3) produced water. The objective of the survey is to develop more current information on the waste volumes and disposal methods used during 1986 through 1991. The possible treatment scenarios for produced water have been identified. Organic and inorganic contaminant removal, liquid/solid separation and liquid/emulsified oil separation have been identified as the main objectives of the treatment of produced water.

  18. Calculation of energy recovery and greenhouse gas emission reduction from palm oil mill effluent treatment by an anaerobic granular-sludge process.

    PubMed

    Show, K Y; Ng, C A; Faiza, A R; Wong, L P; Wong, L Y

    2011-01-01

    Conventional aerobic and low-rate anaerobic processes such as pond and open-tank systems have been widely used in wastewater treatment. In order to improve treatment efficacy and to avoid greenhouse gas emissions, conventional treatment can be upgraded to a high performance anaerobic granular-sludge system. The anaerobic granular-sludge systems are designed to capture the biogas produced, rendering a potential for claims of carbon credits under the Kyoto Protocol for reducing emissions of greenhouse gases. Certified Emission Reductions (CERs) would be issued, which can be exchanged between businesses or bought and sold in international markets at the prevailing market prices. As the advanced anaerobic granular systems are capable of handling high organic loadings concomitant with high strength wastewater and short hydraulic retention time, they render more carbon credits than other conventional anaerobic systems. In addition to efficient waste degradation, the carbon credits can be used to generate revenue and to finance the project. This paper presents a scenario on emission avoidance based on a methane recovery and utilization project. An example analysis on emission reduction and an overview of the global emission market are also outlined. PMID:22170839

  19. Calculation of energy recovery and greenhouse gas emission reduction from palm oil mill effluent treatment by an anaerobic granular-sludge process.

    PubMed

    Show, K Y; Ng, C A; Faiza, A R; Wong, L P; Wong, L Y

    2011-01-01

    Conventional aerobic and low-rate anaerobic processes such as pond and open-tank systems have been widely used in wastewater treatment. In order to improve treatment efficacy and to avoid greenhouse gas emissions, conventional treatment can be upgraded to a high performance anaerobic granular-sludge system. The anaerobic granular-sludge systems are designed to capture the biogas produced, rendering a potential for claims of carbon credits under the Kyoto Protocol for reducing emissions of greenhouse gases. Certified Emission Reductions (CERs) would be issued, which can be exchanged between businesses or bought and sold in international markets at the prevailing market prices. As the advanced anaerobic granular systems are capable of handling high organic loadings concomitant with high strength wastewater and short hydraulic retention time, they render more carbon credits than other conventional anaerobic systems. In addition to efficient waste degradation, the carbon credits can be used to generate revenue and to finance the project. This paper presents a scenario on emission avoidance based on a methane recovery and utilization project. An example analysis on emission reduction and an overview of the global emission market are also outlined.

  20. Characterization of oil and gas waste disposal practices and assessment of treatment costs. Technical progress report, January 1, 1994--March 31, 1994

    SciTech Connect

    Bedient, P.B.

    1994-04-25

    This report covers work completed during the sixth quarter for the project. The project consists of three tasks: the first relates to developing a database of waste volumes and disposal methods used by the industry; the second and third tasks are aimed at investigating technologies that could be used for the treatment of produced waters and developing cost estimates for those technologies. The remainder of this report describes progress related to the three tasks in the project. Overall, construction of the Production Environmental Database (PED) is ongoing. While much of the data has been collected and entered into the database, a few data categories are still missing, for example, soils and geology and geohydrology. Work is currently under way to collect these data. In addition, a detailed data analysis has begun in order to develop relationships between oil and gas activities and environmental characteristics. In terms of the treatment of produced water, much of the work in the past quarter was focused on analyzing the costs associated with the treatment and disposal of waste residuals such as sludges.

  1. Cattle slurry treatment by screw press separation and chemically enhanced settling: effect on greenhouse gas emissions after land spreading and grass yield.

    PubMed

    Fangueiro, David; Senbayran, Mehmet; Trindade, Henrique; Chadwick, David

    2008-10-01

    Five cattle slurry fractions with distinct characteristics were obtained using a combined separation process (screw press+chemically enhanced settling using polyacrylamide (PAM)). The purpose of the present study was to assess the effect of each fraction relatively to the untreated slurry (US) on the emissions of greenhouse gases (CH4, N2O) after grassland application and on the grass yield. Methane emissions occurred mainly in the first two days after application and were observed only in treatments with the US and liquid fractions. Significant N2O emissions were observed only in the US and liquid fractions treatments. A significant increase of the grass yield relatively to the US was observed in plots amended with the composted solid fraction and with the PAM-sup fraction resulting from the PAM sediment settling of the liquid fraction previously obtained by screw press separation, whereas in all other treatments, no significant differences were observed. Considering the overall separation process, the proposed scheme did not lead to an increase, relative to the US, of gas emissions after soil application of the fractions obtained except in the case of CH4 where a small increase was observed.

  2. Do circulating long non-coding RNAs (lncRNAs) (LincRNA-p21, GAS 5, HOTAIR) predict the treatment response in patients with head and neck cancer treated with chemoradiotherapy?

    PubMed

    Fayda, Merdan; Isin, Mustafa; Tambas, Makbule; Guveli, Murat; Meral, Rasim; Altun, Musa; Sahin, Dilek; Ozkan, Gozde; Sanli, Yasemin; Isin, Husniye; Ozgur, Emre; Gezer, Ugur

    2016-03-01

    Long non-coding RNAs (lncRNAs) have been shown to be aberrantly expressed in head and neck cancer (HNC). The aim of the present study was to evaluate plasma levels of three lncRNA molecules (lincRNA-p21, GAS5, and HOTAIR) in the treatment response in HNC patients treated with radical chemoradiotherapy (CRT). Forty-one patients with HNC were enrolled in the study. Most of the patients had nasopharyngeal carcinoma (n = 27, 65.9 %) and locally advanced disease. Blood was drawn at baseline and treatment evaluation 4.5 months after therapy. lncRNAs in plasma were measured by semiquantitative PCR. Treatment response was evaluated according to clinical examination, RECIST and PERCIST criteria based on magnetic resonance imaging (MRI), and positron emission tomography with computed tomography (PET/CT) findings. Complete response (CR) rates were 73.2, 36.6, and 50 % for clinical investigation, PET/CT-, or MRI-based response evaluation, respectively. Predictive value of lncRNAs was investigated in patients with CR vs. those with partial response (PR)/progressive disease (PD). We found that post-treatment GAS5 levels in patients with PR/PD were significantly higher compared with patients with CR based on clinical investigation (p = 0.01). Receiver operator characteristic (ROC) analysis showed that at a cutoff value of 0.3 of GAS5, sensitivity and specificity for clinical tumor response were 82 and 77 %, respectively. Interestingly, pretreatment GAS5 levels were significantly increased in patients with PR/PD compared to those with CR upon MRI-based response evaluation (p = 0.042). In contrast to GAS5, pretreatment or post-treatment lincRNA-p21 and HOTAIR levels were not informative for treatment response. Our results suggest that circulating GAS5 could be a biomarker in predicting treatment response in HNC patients.

  3. JV TASK 7-FIELD APPLICATION OF THE FREEZE-THAW/EVAPORATION (FTE) PROCESS FOR THE TREATMENT OF NATURAL GAS PRODUCED WATER IN WYOMING

    SciTech Connect

    James A. Sorensen; John Boysen; Deidre Boysen; Tim Larson

    2002-10-01

    The freeze-thaw/evaporation (FTE{reg_sign}) process treats oil and gas produced water so that the water can be beneficially used. The FTE{reg_sign} process is the coupling of evaporation and freeze-crystallization, and in climates where subfreezing temperatures seasonally occur, this coupling improves process economics compared to evaporation alone. An added benefit of the process is that water of a quality suited for a variety of beneficial uses is produced. The evolution, from concept to successful commercial deployment, of the FTE{reg_sign} process for the treatment of natural gas produced water has now been completed. In this document, the histories of two individual commercial deployments of the FTE{reg_sign} process are discussed. In Wyoming, as in many other states, the permitting and regulation of oil and gas produced water disposal and/or treatment facilities depend upon the legal relationship between owners of the facility and the owners of wells from which the water is produced. An ''owner-operated'' facility is regulated by the Wyoming Oil and Gas Conservation Commission (WOGCC) and is defined as an entity which only processes water which comes from the wells in fields of which they have an equity interest. However, if a facility processes water from wells in which the owners of the facility have no equity interest, the facility is considered a ''commercial'' facility and is permitted and regulated by the Wyoming Department of Environmental Quality. For this reason, of the two commercial FTE{reg_sign} process deployments discussed in this document, one is related to an ''owner-operated'' facility, and the other relates to a ''commercial'' facility. Case 1 summarizes the permitting, design, construction, operation, and performance of the FTE{reg_sign} process at an ''owner-operated'' facility located in the Jonah Field of southwestern Wyoming. This facility was originally owned by the McMurry Oil Company and was later purchased by the Alberta Energy

  4. Strengthening of oxidation resistant materials for gas turbine applications. [treatment of silicon ceramics for increased flexural strength and impact resistance

    NASA Technical Reports Server (NTRS)

    Kirchner, H. P.

    1974-01-01

    Silicon nitride and silicon carbide ceramics were treated to form compressive surface layers. On the silicon carbide, quenching and thermal exposure treatments were used, and on the silicon nitride, quenching, carburizing, and a combination of quenching and carburizing were used. In some cases substantial improvements in impact resistance and/or flexural strength were observed. The presence of compressive surface stresses was demonstrated by slotted rod tests.

  5. Influence of gas and treatment time on the surface modification of EPDM rubber treated at afterglow microwave plasmas

    NASA Astrophysics Data System (ADS)

    da Maia, J. V.; Pereira, F. P.; Dutra, J. C. N.; Mello, S. A. C.; Becerra, E. A. O.; Massi, M.; Sobrinho, A. S. da Silva

    2013-11-01

    The ethylene propylene diene monomer (EPDM) rubber possesses excellent physical/chemical bulk properties, is cost-effective, and has been used in the mechanical and aerospace industry. However, it has an inert surface and needs a surface treatment in order to improve its adhesion properties. Plasma modification is the most accepted technique for surface modification of polymers without affecting the properties of the bulk. In this study, an afterglow microwave plasma reactor was used to generate the plasma species responsible for the EPDM surface modification. The plasma modified surfaces were analyzed by means of contact angle measurement, adhesion tests, attenuated total reflection-infrared spectroscopy, X-ray photoelectron spectroscopy and scanning electron microscopy. Two experimental variables were analyzed: type of the plasma gases and exposure time were considered. The predominant failure mode was adhesive, for long treatment times a mixture of adhesive and cohesive failure can be observed and the best conditions tested there was an increase of the rupture strength of about 27%, that can be associated mainly with the creation of oxygen containing functional groups on the rubber surface (CO, COC and CO) identified by spectroscopic methods. The predominant failure mode was adhesive, for long treatment times a mixture of adhesive and cohesive failure can be observed. In various conditions tested the contact angles easily decreased more than 500%. What can be concluded that high wettability is a necessary condition to obtain good adhesion, but this is not a sufficient condition.

  6. Technical potential of electricity production from municipal solid waste disposed in the biggest cities in Brazil: landfill gas, biogas and thermal treatment.

    PubMed

    de Souza, Samuel Nm; Horttanainen, Mika; Antonelli, Jhonatas; Klaus, Otávia; Lindino, Cleber A; Nogueira, Carlos Ec

    2014-10-01

    This article presents an analysis of possibilities for electrical energy production by using municipal solid waste disposed in the biggest Brazilian cities. Currently, the municipal solid waste in Brazil is collected and disposed of at landfills, but there are also other technologies, which in addition to dealing with the garbage can also provide benefits in terms of energy provision. The following scenarios were studied in this work: electricity production from landfill gas (reference scenario); incineration of all municipal solid waste; anaerobic digestion of organic waste and incineration of refuse-derived fuel fractions after being separated in separation plants. According to this study, the biggest cities in Brazil generate about 18.9 million tonnes of municipal solid waste per year (2011), of which 51.5% is biogenic matter. The overall domestic consumption of electricity is 480,120 GWh y(-1) in Brazil and the municipal solid waste incineration in the 16 largest cities in the country could replace 1.8% of it using incinerators. The city of São Paulo could produce 637 GWh y(-1) with landfill gas, 2368 GWh y(-1) with incineration of municipal solid waste and 1177 GWh y(-1) with incineration of refuse-derived fuel. The latter two scenarios could replace 27% and 13.5% of the residential electrical energy consumption in the city. This shows that thermal treatment might be a viable option of waste-to-energy in Brazil.

  7. Technical potential of electricity production from municipal solid waste disposed in the biggest cities in Brazil: landfill gas, biogas and thermal treatment.

    PubMed

    de Souza, Samuel Nm; Horttanainen, Mika; Antonelli, Jhonatas; Klaus, Otávia; Lindino, Cleber A; Nogueira, Carlos Ec

    2014-10-01

    This article presents an analysis of possibilities for electrical energy production by using municipal solid waste disposed in the biggest Brazilian cities. Currently, the municipal solid waste in Brazil is collected and disposed of at landfills, but there are also other technologies, which in addition to dealing with the garbage can also provide benefits in terms of energy provision. The following scenarios were studied in this work: electricity production from landfill gas (reference scenario); incineration of all municipal solid waste; anaerobic digestion of organic waste and incineration of refuse-derived fuel fractions after being separated in separation plants. According to this study, the biggest cities in Brazil generate about 18.9 million tonnes of municipal solid waste per year (2011), of which 51.5% is biogenic matter. The overall domestic consumption of electricity is 480,120 GWh y(-1) in Brazil and the municipal solid waste incineration in the 16 largest cities in the country could replace 1.8% of it using incinerators. The city of São Paulo could produce 637 GWh y(-1) with landfill gas, 2368 GWh y(-1) with incineration of municipal solid waste and 1177 GWh y(-1) with incineration of refuse-derived fuel. The latter two scenarios could replace 27% and 13.5% of the residential electrical energy consumption in the city. This shows that thermal treatment might be a viable option of waste-to-energy in Brazil. PMID:25323146

  8. Gas release in the process of thermal treatment of sputtered Pb(Ti0.48Zr0.52)O x films

    NASA Astrophysics Data System (ADS)

    Znamenskii, A. G.; Ionov, A. M.; Marchenko, V. A.

    2016-06-01

    The conditions (regimes of deposition and thermal treatment) for gas bubble formation in ferroelectric Pb(Ti1- y Zr y )O3 films have been determined by thermal desorption and electron and optical micros-copy. A mechanism of bubble formation has been proposed. This mechanism rests upon the notion that lead can form oxides of the PbO2 type with a high oxygen content at relatively low temperatures and that these oxides break down with the release of oxygen to lower oxides of the PbO type upon subsequent heating. These ideas have been taken as the basis of a technique for the fabrication of Pb(Ti1- y Zr y )O3 films with a reduced (by an order of magnitude) density of through defects.

  9. Quantification of synthetic organic chemicals in biological treatment process effluent using solid-phase microextraction and gas chromatography

    SciTech Connect

    Magbanua, B.S. Jr.; Mitchell, D.R.; Fehniger, S.M.; Bowyer, R.L.; Grady, C.P.L. Jr.

    2000-02-01

    Solid-phase microextraction (SPME), a technique that uses a polymer-coated, fused-silica fiber to selectively extract organic analyses from a sample matrix, followed by gas chromatography (GC), was used to quantify selected synthetic organic chemicals (SOCs) in biological reactor effluent. By selecting an appropriate combination of SPME fiber, GC column, and GC detector, assays to quantify either a suite of SOCs or single selected SOCs were developed. Phenol, 4-chlorophenol, 2-nitrophenol, 4-nitrophenol, 2,4,-dinitrophenol, isophorone, m-toluate, m-sylene, and di-n-butylphthalate were quantified simultaneously using an 85-{micro}m polyacrylate SPME fiber, a 5% diphenyl-95% dimethyl polysiloxane capillary column, and a flame ionization detector. m-Xylene was quantified using a 100-{micro}m polydimethylsiloxane SPME fiber, a 5% diphenyl-95% dimethyl polysiloxane capillary column, and a mass spectrometric detector. Dichloromethane was quantified using an 85-{micro}m polyacrylate SPME fiber, a Carbopack B/1% SP-1000 packed column, and an electron capture detector. All three assays enabled detection of the target analyses to low concentrations ({micro}g/L) with minimal sample volume and processing requirements.

  10. THE RELATION BETWEEN GAS DENSITY AND VELOCITY POWER SPECTRA IN GALAXY CLUSTERS: QUALITATIVE TREATMENT AND COSMOLOGICAL SIMULATIONS

    SciTech Connect

    Zhuravleva, I.; Allen, S. W.; Churazov, E. M.; Gaspari, M.; Schekochihin, A. A.; Lau, E. T.; Nagai, D.; Nelson, K.; Parrish, I. J.

    2014-06-10

    We address the problem of evaluating the power spectrum of the velocity field of the intracluster medium using only information on the plasma density fluctuations, which can be measured today by Chandra and XMM-Newton observatories. We argue that for relaxed clusters there is a linear relation between the rms density and velocity fluctuations across a range of scales, from the largest ones, where motions are dominated by buoyancy, down to small, turbulent scales: (δρ{sub k}/ρ){sup 2}=η{sub 1}{sup 2}(V{sub 1,k}/c{sub s}){sup 2}, where δρ {sub k}/ρ is the spectral amplitude of the density perturbations at wavenumber k, V{sub 1,k}{sup 2}=V{sub k}{sup 2}/3 is the mean square component of the velocity field, c{sub s} is the sound speed, and η{sub 1} is a dimensionless constant of the order of unity. Using cosmological simulations of relaxed galaxy clusters, we calibrate this relation and find η{sub 1} ≈ 1 ± 0.3. We argue that this value is set at large scales by buoyancy physics, while at small scales the density and velocity power spectra are proportional because the former are a passive scalar advected by the latter. This opens an interesting possibility to use gas density power spectra as a proxy for the velocity power spectra in relaxed clusters across a wide range of scales.

  11. Metabolomic investigation of porcine muscle and fatty tissue after Clenbuterol treatment using gas chromatography/mass spectrometry.

    PubMed

    Li, Guanglei; Fu, Yuhua; Han, Xiaosong; Li, Xinyun; Li, Changchun

    2016-07-22

    Clenbuterol is a β-adrenergic agonist used as additive to increase the muscle mass of meat-producing animals. Previous studies were limited to evaluations of animal growth performance and determination of the residues. Several studies have focused on urine samples. Little information about the underlying molecular mechanisms that can explain Clenbuterol metabolism and promote energy repartition in animal muscle and fatty tissue is available. Therefore, this research aims to detect the metabolite variations in muscle and fatty tissue acquired from Chinese pigs fed with Clenbuterol using gas chromatography/mass spectrometry (GC/MS). Ten two-month old Enshi black pigs were fed under the same condition; five of which were fed with basic ration containing Clenbuterol for one month, whereas the other five pigs were fed only with basic ration. Muscle and fatty tissue were subjected to metabolomics analysis using GC/MS. Differences in metabolomic profiles between the two groups were characterized by multivariate statistical analysis. The muscle samples showed that 15 metabolites were significantly different in the Clenbuterol-treated group compared with the control group; 13 potential biomarkers were found in the fatty tissue. Most of the metabolites were associated with fatty acid metabolism and amino acid metabolism. Glycerol, phenylalanine, and leucine were the common metabolites between the muscle and fatty tissue. These metabolites may provide a new clue that contributes to the understanding of the energy reassignment induced by Clenbuterol. PMID:27320379

  12. Effect of sulfur hexafluoride gas and post-annealing treatment for inductively coupled plasma etched barium titanate thin films

    PubMed Central

    2014-01-01

    Aerosol deposition- (AD) derived barium titanate (BTO) micropatterns are etched via SF6/O2/Ar plasmas using inductively coupled plasma (ICP) etching technology. The reaction mechanisms of the sulfur hexafluoride on BTO thin films and the effects of annealing treatment are verified through X-ray photoelectron spectroscopy (XPS) analysis, which confirms the accumulation of reaction products on the etched surface due to the low volatility of the reaction products, such as Ba and Ti fluorides, and these residues could be completely removed by the post-annealing treatment. The exact peak positions and chemicals shifts of Ba 3d, Ti 2p, O 1 s, and F 1 s are deduced by fitting the XPS narrow-scan spectra on as-deposited, etched, and post-annealed BTO surfaces. Compared to the as-deposited BTOs, the etched Ba 3d 5/2 , Ba 3d 3/2 , Ti 2p 3/2 , Ti 2p 1/2 , and O 1 s peaks shift towards higher binding energy regions by amounts of 0.55, 0.45, 0.4, 0.35, and 0.85 eV, respectively. A comparison of the as-deposited film with the post-annealed film after etching revealed that there are no significant differences in the fitted XPS narrow-scan spectra except for the slight chemical shift in the O 1 s peak due to the oxygen vacancy compensation in O2-excessive atmosphere. It is inferred that the electrical properties of the etched BTO film can be restored by post-annealing treatment after the etching process. Moreover, the relative permittivity and loss tangent of the post-annealed BTO thin films are remarkably improved by 232% and 2,695%, respectively. PMID:25249824

  13. Treatment of waste gas containing low concentration of dimethyl sulphide (DMS) in a bench-scale biofilter.

    PubMed

    Giri, B S; Mudliar, S N; Deshmukh, S C; Banerjee, S; Pandey, R A

    2010-04-01

    Biological treatment of dimethyl sulphide (DMS) was investigated in a bench-scale biofilter, packed with compost along with wood chips, and enriched with DMS degrading microorganism Bacillus sphaericus. The biofilter could remove 62-74% of the inlet DMS, at an optimum loading of 0.484 g/m(3)/h with optimum empty bed contact time (EBCT) of 384 s and an average moisture range of 65-70%. The biodegradative products of DMS were sulphide, thiosulphate and sulphate. Evaluation of microbiological status of the biofilter indicated the presence of other bacterial cultures viz. Paenibacillus polymyxa, and Bacillus megaterium, besides B. sphaericus. PMID:20006492

  14. Application of strategies for sanitation management in wastewater treatment plants in order to control/reduce greenhouse gas emissions.

    PubMed

    Préndez, Margarita; Lara-González, Scarlette

    2008-09-01

    Greenhouse gases (GHG), basically methane (CH(4)), carbon dioxide (CO(2)) and nitrous oxide (N(2)O), occur at atmospheric concentrations of ppbv to ppmv under natural conditions. GHG have long mean lifetimes and are an important factor for the mean temperature of the Earth. However, increasing anthropogenic emissions could produce a scenario of progressive and cumulative effects over time, causing a potential "global climate change". Biological degradation of the organic matter present in wastewater is considered one of the anthropogenic sources of GHG. In this study, GHG emissions for the period 1990-2027 were estimated considering the sanitation process and the official domestic wastewater treatment startup schedule approved for the Metropolitan Region (MR) of Santiago, Chile. The methodology considers selected models proposed by the Intergovernmental Panel on Climate Change (IPCC) and some others published by different authors; these were modified according to national conditions and different sanitation and temporal scenarios. For the end of the modeled period (2027), results show emissions of about 65 Tg CO(2) equiv./year (as global warming potential), which represent around 50% of national emissions. These values could be reduced if certain sanitation management strategies were introduced in the environmental management by the sanitation company in charge of wastewater treatment.

  15. Landau Damping and Anomalous Skin Effect in Low-pressure Gas Discharges: Self-consistent Treatment of Collisionless Heating

    SciTech Connect

    Igor D. Kaganovich; Oleg V. Polomarov; Constantine E. Theodosiou

    2004-01-30

    In low-pressure discharges, where the electron mean free path is larger or comparable with the discharge length, the electron dynamics is essentially nonlocal. Moreover, the electron energy distribution function (EEDF) deviates considerably from a Maxwellian. Therefore, an accurate kinetic description of the low-pressure discharges requires knowledge of the nonlocal conductivity operator and calculation of the non-Maxwellian EEDF. The previous treatments made use of simplifying assumptions: a uniform density profile and a Maxwellian EEDF. In the present study a self-consistent system of equations for the kinetic description of nonlocal, nonuniform, nearly collisionless plasmas of low-pressure discharges is reported. It consists of the nonlocal conductivity operator and the averaged kinetic equation for calculation of the non-Maxwellian EEDF. This system was applied to the calculation of collisionless heating in capacitively and inductively coupled plasmas. In particular, the importance of accounting for the nonuniform plasma density profile for computing the current density profile and the EEDF is demonstrated. The enhancement of collisionless heating due to the bounce resonance between the electron motion in the potential well and the external radio-frequency electric field is investigated. It is shown that a nonlinear and self-consistent treatment is necessary for the correct description of collisionless heating.

  16. Quantitative molecular biology and gas flux measurements demonstrate soil treatment and depth affects on the distribution and activity of denitrifiers

    NASA Astrophysics Data System (ADS)

    Barrett, M. M.; Jahangir, M.; Cardenas, L.; Khalil, M.; Richards, K. R.; O'Flaherty, V.

    2010-12-01

    The growing industrialisation of agriculture has led to a dramatic increase in organic and inorganic nitrogen (N) fertiliser inputs to agro-ecosystems. This increase has had negative effects on the quality of water ecosystems and greenhouse gas emissions.The study objective was to quantify denitrification and denitrifying microorganisms, using real-time PCR assays of the nitrite reductase(nir) and nitrous oxide reductase(nos) functional gene copy concentrations (GCC g[soil]-1) in Irish agricultural surface and subsoils. Soil cores from 3 soil horizons (A:0-10 cm; B:45-55 cm; C:120-130cm) were amended with 3 alternate N- and C-source amendments (NO3-; NO3-+glucose-C; NO3-+Dissolved Organic Carbon (DOC). Real-time production of N2O and N2 was recorded by gas chromatography in a specialized He/O2 environment. N2O and Total Denitrification (TDN) (N2O+N2) production was generally greater in surface soil (2.052 mg/kg/d TDN) than in subsoils (0.120 mg/kg/d TDN). The abundance of denitrifying nirS, nirK (nir) and nos genes was higher in the surface soil, decreasing with soil depth, except in incubations amended with NO3- and DOC, where the carbon source directly positively affected gene copy numbers and fluxes of N2O and N2 production. C addition increased soil denitrification rates, and resulted in higher N2O/(N2O+N2) ratios in surface soil (0.39) than subsoils (0.005), indicating that the subsoil had higher potential for complete reduction of N2O to N2. In the subsoils, complete reduction of NO3- due to glucose-C and DOC addition was observed. Interestingly, at all 3 soil depths, lower nirK abundance (2.78 105 GCC) was recorded, compared to nirS (1.45 107 GCC), but the overall abundance of nir (S+K) i.e. (1.54 107GCC), corresponded with N2O emission fluxes (3.34 mg/kg/d) Statistical analysis indicates negative correlation between nirK GCC and N2O production, but a strong positive correlation was observed between nirS GCC and N2O. We therefore hypothesize that the

  17. Wetland treatment of oil and gas well wastewaters. Quarterly technical report, November 25, 1993--March 24, 1994

    SciTech Connect

    Kadlec, R.H.; Srinivasan, K.R.

    1994-04-15

    In the third quarterly report, adsorption of heavy metals ions such as Cu(II) and Cr(VI) onto soils drawn from the laboratory-type wetland (LW) was shown to be weak. On the other hand, it was shown that modified-clays did adsorb Cr(VI) ions strongly at pH 4.5. Further, studies on the pH dependence of the adsorption of {beta}-naphthoic acid, (NA), a well-documented contaminant in many oil and gas well waste waters (4), onto modified-clays were undertaken and it was shown that uptake of NA by modified-clays was of the high affinity type at pH 4.5 and 7.0, but weak at pH 9.0. Adsorption of heavy metal ions, Cu{sup 2+}, and CR(VI) onto algae, a proposed wetland amendment, was carried out and the results were presented and discussed in the fourth quarterly report. Studies on the dynamics of uptake of phenol and NA by laboratory-type wetlands (LWs) were initiated and preliminary results indicated that both phenol and NA were sorbed onto components of LWs. A mass balance model has been developed to quantify the fate of phenol in LWs. The model is based on the postulate that the fate of phenol in LWs can be attributed to a combination of (1) evaporation of solute and solvent, (2) adsorption of phenol onto various components of LW and (3) its biodegradation, both in solution and at solid-liquid interface. As an initial approximation, the latter two processes have been lumped together and incorporated into the model as an unit operation. Both zero order and first order kinetics for the disappearance of phenol have been considered. Evaporative losses of water and phenol have also been taken into account and this model is presented and discussed in this quarterly report.

  18. Estimates of global greenhouse gas emissions from industrial and domestic wastewater treatment. Final report, September 1994-March 1997

    SciTech Connect

    Doorn, M.R.J.; Strait, R.P.; Barnard, W.R.; Eklund, B.

    1997-09-01

    The report summarizes the findings of field tests and provides emission factors for methane (CH4) and nitorus oxide (N2O) from wastewater treatment (WWT). It also includes country-specific activity data on industrial and domestic WWT which were used to develop country-specific emission estimates for CH4 and N2O. The report concludes that WWT is unlikely to be a significant source of volatile organic carbon and carbon dioxide emissions. The biggest contributor to industrial CH4 emissions from WWT is the pulp and paper industry in developing and Eastern European countries. The second principal contributor to CH4 emissions from WWT is the meat and poultry industry. Russia is believed to be the largest contributor. CH4 emissions from untreated domestic wastewater may be many times higher than those of treated wastewater. The report provides rough estimates for global N2O emissions from WWT.

  19. Monitoring of sixteen fragrance allergens and two polycyclic musks in wastewater treatment plants by solid phase microextraction coupled to gas chromatography.

    PubMed

    Godayol, Anna; Besalú, Emili; Anticó, Enriqueta; Sanchez, Juan M

    2015-01-01

    A methodology based on headspace solid phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) determination was developed for the monitoring and evaluation of the removal efficiency of 16 common fragrance allergens and two polycyclic musks in wastewater treatment plants (WWTPs). An experimental design with a full factorial model was applied to evaluate the effects of the experimental parameters on the extraction (e.g., salt content, time and extraction temperature). After determining the optimum conditions (2.4 g NaCl, 45 min at 90 °C), an external calibration was performed and quality parameters of the proposed method were evaluated. Method detection limits in the range of 0.01-1.7 μg L(-1) were obtained. Satisfactory inter-day precision values between 4% and 23% (n=5) were obtained for most compounds. The method was applied to the monitoring of the target analytes in samples from two WWTPs. Seven target compounds were detected at the primary effluent of both plants at μg L(-1) levels. Limonene, linalool and eugenol were quantitatively eliminated during the secondary treatments of both WWTPs, while lilial, benzyl salicylate, galaxolide, and tonalide were still detected at the effluent waters.

  20. 4-Nitrophenol, 1-nitropyrene, and 9-nitroanthracene emissions in exhaust particles from diesel vehicles with different exhaust gas treatments

    NASA Astrophysics Data System (ADS)

    Inomata, Satoshi; Fushimi, Akihiro; Sato, Kei; Fujitani, Yuji; Yamada, Hiroyuki

    2015-06-01

    The dependence of nitro-organic compound emissions in automotive exhaust particles on the type of aftertreatment used was investigated. Three diesel vehicles with different aftertreatment systems (an oxidation catalyst, vehicle-DOC; a particulate matter and NOx reduction system, vehicle-DPNR; and a urea-based selective catalytic reduction system, vehicle-SCR) and a gasoline car with a three-way catalyst were tested. Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs) and nitrophenols in the particles emitted were analyzed by thermal desorption gas chromatography/mass spectrometry and liquid chromatography/mass spectrometry. The secondary production of nitro-organic compounds on the filters used to collect particles and the adsorption of gaseous nitro-organic compounds by the filters were evaluated. Emissions of 1-nitropyrene, 9-nitroanthracene, and 4-nitrophenol in the diesel exhaust particles were then quantified. The NOx reduction process in vehicle-DPNR appeared to remove nitro-hydrocarbons efficiently but not to remove nitro-oxygenated hydrocarbons efficiently. The nitro-PAH emission factors were lower for vehicle-DOC when it was not fitted with a catalyst than when it was fitted with a catalyst. The 4-nitrophenol emission factors were also lower for vehicle-DOC with a catalyst than vehicle-DOC without a catalyst, suggesting that the oxidation catalyst was a source of both nitro-PAHs and 4-nitrophenol. The time-resolved aerosol mass spectrometry data suggested that nitro-organic compounds are mainly produced when an engine is working under load. The presence of 4-nitrophenol in the particles was not confirmed statistically because of interference from gaseous 4-nitrophenol. Systematic errors in the estimated amounts of gaseous 1-nitropyrene and 9-nitroanthracene adsorbed onto the filters and the estimated amounts of volatile nitro-organic compounds that evaporated during sampling and during post-sampling conditioning could not be excluded. An analytical method

  1. The potential and realistic hazards after a solar-driven chemical treatment of benzene using a health risk assessment at a gas station site in Korea.

    PubMed

    Cho, Il-Hyoung; Chang, Soon-Woong

    2008-01-01

    In order to evaluate the potential use for ex situ remediation, a solar-driven, photocatalyzed reactor system was constructed and applied for the treatment of groundwater contaminated with benzene using selected advanced oxidation processes (AOP) processes, such as H(2)O(2)/solar light, TiO(2) slurry/solar light and immobilized TiO(2)/solar light. However; to date, there have been few attempts to characterize the potential impact of residual levels of benzene on human health after treatment. Some papers have focused on the application of treatment methods of benzene, but most have not considered the effects of realistic hazards and human health. Therefore, potential and realistic hazards of benzene to human health were investigated at a gas station site using a risk-based assessment approach. Among the different remediation actions, the solar light/TiO(2) slurry/H(2)O(2) system (Action 5) showed higher removal efficiency than the solar light/TiO(2) slurry (Action 3) and the solar light/immobilized TiO(2) (Action 2) systems for the treatment of benzene. The Action 5 remediation method achieved 98% degradation, and lead to a substantial increase in the removal of benzene due to the synergetic effect of TiO(2) with the oxidant, H(2)O(2). Also, using the realistic and potential hazard assessment instead of the point estimation of concentration after benzene treatment, the total health risk exceeded the target risk value (1 x 10(-6)). However, the 95th percentile target cancer risk, found using a probabilistic analysis (Monte Carlo method), was around 1 x 10(-6), indicating a low potential carcinogenic risk. Therefore, it was concluded that no adverse health risk was unlikely to be posed if the Action 5 system, which included the addition of TiO(2) and H(2)O(2), or if an increased reaction time was applied. In addition, continuous efforts and proper actions must be taken on the "Soil and Groundwater Remediation Action" based on the risk assessment in Korea.

  2. Co-precipitation of radium with barium and strontium sulfate and its impact on the fate of radium during treatment of produced water from unconventional gas extraction.

    PubMed

    Zhang, Tieyuan; Gregory, Kelvin; Hammack, Richard W; Vidic, Radisav D

    2014-04-15

    Radium occurs in flowback and produced waters from hydraulic fracturing for unconventional gas extraction along with high concentrations of barium and strontium and elevated salinity. Radium is often removed from this wastewater by co-precipitation with barium or other alkaline earth metals. The distribution equation for Ra in the precipitate is derived from the equilibrium of the lattice replacement reaction (inclusion) between the Ra(2+) ion and the carrier ions (e.g., Ba(2+) and Sr(2+)) in aqueous and solid phases and is often applied to describe the fate of radium in these systems. Although the theoretical distribution coefficient for Ra-SrSO4 (Kd = 237) is much larger than that for Ra-BaSO4 (Kd = 1.54), previous studies have focused on Ra-BaSO4 equilibrium. This study evaluates the equilibria and kinetics of co-precipitation reactions in Ra-Ba-SO4 and Ra-Sr-SO4 binary systems and the Ra-Ba-Sr-SO4 ternary system under varying ionic strength (IS) conditions that are representative of brines generated during unconventional gas extraction. Results show that radium removal generally follows the theoretical distribution law in binary systems and is enhanced in the Ra-Ba-SO4 system and restrained in the Ra-Sr-SO4 system by high IS. However, the experimental distribution coefficient (Kd') varies widely and cannot be accurately described by the distribution equation, which depends on IS, kinetics of carrier precipitation and does not account for radium removal by adsorption. Radium removal in the ternary system is controlled by the co-precipitation of Ra-Ba-SO4, which is attributed to the rapid BaSO4 nucleation rate and closer ionic radii of Ra(2+) with Ba(2+) than with Sr(2+). Carrier (i.e., barite) recycling during water treatment was shown to be effective in enhancing radium removal even after co-precipitation was completed. Calculations based on experimental results show that Ra levels in the precipitate generated in centralized waste treatment facilities far

  3. Co-precipitation of radium with barium and strontium sulfate and its impact on the fate of radium during treatment of produced water from unconventional gas extraction.

    PubMed

    Zhang, Tieyuan; Gregory, Kelvin; Hammack, Richard W; Vidic, Radisav D

    2014-04-15

    Radium occurs in flowback and produced waters from hydraulic fracturing for unconventional gas extraction along with high concentrations of barium and strontium and elevated salinity. Radium is often removed from this wastewater by co-precipitation with barium or other alkaline earth metals. The distribution equation for Ra in the precipitate is derived from the equilibrium of the lattice replacement reaction (inclusion) between the Ra(2+) ion and the carrier ions (e.g., Ba(2+) and Sr(2+)) in aqueous and solid phases and is often applied to describe the fate of radium in these systems. Although the theoretical distribution coefficient for Ra-SrSO4 (Kd = 237) is much larger than that for Ra-BaSO4 (Kd = 1.54), previous studies have focused on Ra-BaSO4 equilibrium. This study evaluates the equilibria and kinetics of co-precipitation reactions in Ra-Ba-SO4 and Ra-Sr-SO4 binary systems and the Ra-Ba-Sr-SO4 ternary system under varying ionic strength (IS) conditions that are representative of brines generated during unconventional gas extraction. Results show that radium removal generally follows the theoretical distribution law in binary systems and is enhanced in the Ra-Ba-SO4 system and restrained in the Ra-Sr-SO4 system by high IS. However, the experimental distribution coefficient (Kd') varies widely and cannot be accurately described by the distribution equation, which depends on IS, kinetics of carrier precipitation and does not account for radium removal by adsorption. Radium removal in the ternary system is controlled by the co-precipitation of Ra-Ba-SO4, which is attributed to the rapid BaSO4 nucleation rate and closer ionic radii of Ra(2+) with Ba(2+) than with Sr(2+). Carrier (i.e., barite) recycling during water treatment was shown to be effective in enhancing radium removal even after co-precipitation was completed. Calculations based on experimental results show that Ra levels in the precipitate generated in centralized waste treatment facilities far

  4. Improvement of activated carbons as oxygen reduction catalysts in neutral solutions by ammonia gas treatment and their performance in microbial fuel cells

    NASA Astrophysics Data System (ADS)

    Watson, Valerie J.; Nieto Delgado, Cesar; Logan, Bruce E.

    2013-11-01

    Commercially available activated carbon (AC) powders from different precursor materials (peat, coconut shell, coal, and hardwood) were treated with ammonia gas at 700 °C to improve their performance as oxygen reduction catalysts in neutral pH solutions used in microbial fuel cells (MFCs). The ammonia treated ACs exhibited better catalytic performance in rotating ring-disk electrode tests than their untreated precursors, with the bituminous based AC most improved, with an onset potential of Eonset = 0.12 V (untreated, Eonset = 0.08 V) and n = 3.9 electrons transferred in oxygen reduction (untreated, n = 3.6), and the hardwood based AC (treated, Eonset = 0.03 V, n = 3.3; untreated, Eonset = -0.04 V, n = 3.0). Ammonia treatment decreased oxygen content by 29-58%, increased nitrogen content to 1.8 atomic %, and increased the basicity of the bituminous, peat, and hardwood ACs. The treated coal based AC cathodes had higher maximum power densities in MFCs (2450 ± 40 mW m-2) than the other AC cathodes or a Pt/C cathode (2100 ± 1 mW m-2). These results show that reduced oxygen abundance and increased nitrogen functionalities on the AC surface can increase catalytic performance for oxygen reduction in neutral media.

  5. Rapid determination of methadone and its major metabolite in biological fluids by gas-liquid chromatography with thermionic detection for maintenance treatment of opiate addicts.

    PubMed

    Chikhi-Chorfi, N; Pham-Huy, C; Galons, H; Manuel, N; Lowenstein, W; Warnet, J M; Claude, J R

    1998-11-01

    A rapid gas-liquid chromatographic assay is developed for the quantification of methadone (Mtd) and its major metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), in biological fluids of opiate addicts. After alkaline extraction from samples with lidocaine hydrochloride as internal standard, Mtd and EDDP are separated on SP-2250 column at 220 degrees C and detected with a thermionic detector. The chromatographic time is about 6 min. The relative standard deviations (R.S.D.) of Mtd and EDDP standards are between 1.5 and 5.5%. Most drugs of abuse (morphine, codeine, narcotine, cocaine, benzoylecgonine, cocaethylene, dextropropoxyphene etc) are shown not to interfere with this technique. The method has been applied to study the levels of Mtd and EDDP metabolite in serum, saliva and urine of patients under maintenance treatment for opiate dependence. EDDP levels were found higher than those of Mtd in urine samples from four treated patients, but lower in serum and undetectable in saliva. However, Mtd concentrations were higher in saliva than in serum.

  6. Highly efficient and stable Au/CeO2-TiO2 photocatalyst for nitric oxide abatement: potential application in flue gas treatment.

    PubMed

    Zhu, Wei; Xiao, Shuning; Zhang, Dieqing; Liu, Peijue; Zhou, Hongjun; Dai, Wenrui; Liu, Fanfan; Li, Hexing

    2015-10-01

    In the present work, highly efficient and stable Au/CeO2-TiO2 photocatalysts were prepared by a microwave-assisted solution approach. The Au/CeO2-TiO2 composites with optimal molar ratio of Au/Ce/Ti of 0.004:0.1:1 delivered a remarkably high and stable NO conversion rate of 85% in a continuous flow reactor system under simulated solar light irradiation, which far exceeded the rate of 48% over pure TiO2. The tiny Au nanocrystals (∼1.1 nm) were well stabilized by CeO2 via strong metal-support bonding even it was subjected to calcinations at 550 °C for 6 h. These Au nanocrystals served as the very active sites for activating the molecule of nitric oxide and reducing the transmission time of the photogenerated electrons to accelerate O2 transforming to reactive oxygen species. Moreover, the Au-Ce(3+) interface formed and served as an anchoring site of O2 molecule. Then more adsorbed oxygen could react with photogenerated electrons on TiO2 surfaces to produce more superoxide radicals for NO oxidation, resulting in the improved efficiency. Meanwhile, O2 was also captured at the Au/TiO2 perimeter site and the NO molecules on TiO2 sites were initially delivered to the active perimeter site via diffusion on the TiO2 surface, where they assisted O-O bond dissociation and reacted with oxygen at these perimeter sites. Therefore, these finite Au nanocrystals can consecutively expose active sites for oxidizing NO. These synergistic effects created an efficient and stable system for breaking down NO pollutants. Furthermore, the excellent antisintering property of the catalyst will allow them for the potential application in photocatalytic treatment of high-temperature flue gas from power plant.

  7. Assessment of Fenton's reagent and ozonation as pre-treatments for increasing the biodegradability of aqueous diethanolamine solutions from an oil refinery gas sweetening process.

    PubMed

    Durán-Moreno, A; García-González, S A; Gutiérrez-Lara, M R; Rigas, F; Ramírez-Zamora, R M

    2011-02-28

    The aim of this work was to evaluate the efficiency of three chemical oxidation processes for increasing the biodegradability of aqueous diethanolamine solutions (aqueous DEA solutions), to be used as pre-treatments before a biological process. The raw aqueous DEA solution, sourced from a sour gas sweetening plant at a Mexican oil refinery, was first characterized by standardized physico-chemical methods. Then experiments were conducted on diluted aqueous DEA solutions to test the effects of Fenton's reagent, ozone and ozone-hydrogen peroxide on the removal of some physicochemical parameters of these solutions. Lastly, biodegradability tests based on Dissolved Organic Carbon Die Away OECD301-A, were carried out on a dilution of the raw aqueous DEA solution and on the treated aqueous DEA solutions, produced by applying the best experimental conditions determined during the aforementioned oxidation tests. Experimental results showed that for aqueous DEA solutions treated with Fenton's reagent, the best degradation rate (70%) was obtained at pH 2.8, with Fe(2+) and H(2)O(2) at doses of 1000 and 10,000 mg/L respectively. In the ozone process, the best degradation (60%) was observed in aqueous DEA solution (100 mg COD/L), using 100 mg O(3)/L at pH 5. In the ozone-hydrogen peroxide process, no COD or DOC removals were observed. The diluted spent diethanolamine solution showed its greatest increase in biodegradability after a reaction period of 28 days when treated with Fenton's reagent, but after only 15 days in the case of ozonation.

  8. Former poison gas workers and cancer: incidence and inhibition of tumor formation by treatment with biological response modifier N-CWS.

    PubMed

    Yamakido, M; Ishioka, S; Hiyama, K; Maeda, A

    1996-05-01

    Mustard gas is known to have mutagenic and carcinogenic effects on animal and human cells. In this report, 1,632 male Japanese who worked in poison gas factories at some time between the years 1927 and 1945 were studied to determine comparative risk for development of cancer, the reference population being data on Japanese males overall. The standardized mortality ratio (SMR) for lung cancer in workers directly and indirectly involved in the production of mustard gas was significantly elevated. In addition, SMR for lung cancer in worker who had worked for more than 5 years was also significantly elevated. Thus, poison gas workers who had engaged in the production of mustard gas or related work for more than 5 years are a high-risk group for lung cancer. Under the cancer preventive program, Nocardia rubra cell-wall skeleton (N-CWS) was administered to 146 former poison gas workers. During a 4.5 year observation period, development of cancers was found in 7 treated workers and 17 untreated controls. After elimination of the influence of smoking level, a significant suppression of development of cancers was noted in the N-CWS-treated workers as compared to the untreated controls. Although the molecular mechanisms of carcinogenesis in former poison gas workers remains unclear, our study proposes the possible effect of biological response modifiers in the prevention of cancer development in high-risk human subjects.

  9. Easy landfill gas profits

    SciTech Connect

    Schleifer, R.

    1988-03-01

    Landfill and digester gases can be valuable fuels. Engine-driven energy recovery systems are a common sight today at landfills and wastewater treatment plants. Yet the complaint is still heard: ''Waste'' gases are tough on engines. That can be true when impurities and variability in landfill or digester gas are not controlled. But with today's fuel-system technology, control is not difficult. Typically, custom-engineered fuel systems for alternate-fuel engine applications can include filters, scrubbers, separators, calorimeters, or other devices needed to deliver an acceptable gas to the engine. It's important that this system is designed only after a thorough gas analysis.

  10. Gas gangrene

    MedlinePlus

    Tissue infection - Clostridial; Gangrene - gas; Myonecrosis; Clostridial infection of tissues; Necrotizing soft tissue infection ... Gas gangrene is most often caused by bacteria called Clostridium perfringens. It also can be caused by ...

  11. Gas separating

    DOEpatents

    Gollan, Arye

    1988-01-01

    Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing.

  12. Gas separating

    DOEpatents

    Gollan, Arye Z. [Newton, MA

    1990-12-25

    Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing.

  13. The evaluation of the pyrochemistry for the treatment of Gen IV nuclear fuels Inert matrix chlorination studies in the gas phase or molten chloride salts

    NASA Astrophysics Data System (ADS)

    Bourg, S.; Péron, F.; Lacquement, J.

    2007-01-01

    The structure of the fuels for the future Gen IV nuclear reactors will be totally different from those of PWR, especially for the GFR concept including a closed cycle. In these reactors, fissile materials (carbides or nitrides of actinides) should be surrounded by an inert matrix. In order to build a reprocessing process scheme, the behavior of the potential inert matrices (silicon carbide, titanium nitride, and zirconium carbide and nitride) was studied by hydro- and pyrometallurgy. This paper deals with the chlorination results at high temperature by pyrometallurgy. For the first time, the reactivity of the matrix towards chlorine gas was assessed in the gas phase. TiN, ZrN and ZrC are very reactive from 400 °C whereas it is necessary to be over 900 °C for SiC to be as fast. In molten chloride melts, the bubbling of chlorine gas is less efficient than in gas phase but it is possible to attack the matrices. Electrochemical methods were also used to dissolve the refractory materials, leading to promising results with TiN, ZrN and ZrC. The massive SiC samples used were not conductive enough to be studied and in this case specific SiC-coated carbon electrodes were used. The key point of these studies was to find a method to separate the matrix compounds from the fissile material in order to link the head to the core of the process (electrochemical separation or liquid-liquid reductive extraction in the case of a pyrochemical reprocessing).

  14. Effect of plasma treatments on the steam-sour gas resistance and lubricity of elastomers. [Rubbers used: copoly(ethene-propene); copoly(1,1-difluoroethane-hexafluoropropene); copoly(2-propenenitrile-1,3 butadiene); plasma polymerized tetrafluoroethane

    SciTech Connect

    Arnold, C. Jr.; Bieg, K.W.; Cuthrell, R.E.; Nelson, G.C.

    1982-03-01

    Elastomers are widely used in drilling and logging applications as static seals such as casing packers and dynamic seals such as o-rings for drill bits. Static seals often fail in service because of thermochemical degradation due to the combined effects of steam and sour gas at elevated temperatures that are characteristic of deep wells. Dynamic seals frequently fail because of abrasive wear that occurs even at the low temperatures that prevail in shallow wells. We have shown that improved steam-sour gas resistance of a fully formulated ethylene-propylene rubber at elevated temperatures can be achieved by coating the rubber with a thin film of plasma polymerized tetrafluoroethylene. Thus, no change in the mechanical properties of the coated rubber was observed after exposure to steam and sour gas at 275/sup 0/C for 48 h. In contrast, the shear modulus of the upcoated rubber increased by 96% after the same exposure. While the effectiveness of the fluorocarbon coating decreased at longer exposure times, short-term protection of elastomers could be beneficial in certain logging operations. It was also found that the coefficient of friction of a nitrile rubber (Buna N) was reduced by 20% after treatment with a carbon tetrafluoride plasma. This enhanced lubricity could lead to better wear characteristics in conventional drill bits where the seal is in contact with a moving metal surface. The surfaces of the plasma treated elastomers were characterized by water contact angle, scanning electron microscopy, and electron spectroscopy for chemical analysis.

  15. Air classification: Potential treatment method for optimized recycling or utilization of fine-grained air pollution control residues obtained from dry off-gas cleaning high-temperature processing systems.

    PubMed

    Lanzerstorfer, Christof

    2015-11-01

    In the dust collected from the off-gas of high-temperature processes, usually components that are volatile at the process temperature are enriched. In the recycling of the dust, the concentration of these volatile components is frequently limited to avoid operation problems. Also, for external utilization the concentration of such volatile components, especially heavy metals, is often restricted. The concentration of the volatile components is usually higher in the fine fractions of the collected dust. Therefore, air classification is a potential treatment method to deplete the coarse material from these volatile components by splitting off a fines fraction with an increased concentration of those volatile components. In this work, the procedure of a sequential classification using a laboratory air classifier and the calculations required for the evaluation of air classification for a certain application were demonstrated by taking the example of a fly ash sample from a biomass combustion plant. In the investigated example, the Pb content in the coarse fraction could be reduced to 60% by separation of 20% fines. For the non-volatile Mg the content was almost constant. It can be concluded that air classification is an appropriate method for the treatment of off-gas cleaning residues.

  16. Basic Gas Chlorination Workshop Manual.

    ERIC Educational Resources Information Center

    Ontario Ministry of the Environment, Toronto.

    This manual was developed for use at workshops designed to introduce treatment plant operators to the safe operation and maintenance of gas chlorination systems employing the variable vacuum gas chlorinator. Each of the lessons in this document has clearly stated behavioral objectives to tell the trainee what he should know or do after completing…

  17. Biomass accumulation and clogging in biotrickling filters for waste gas treatment. Evaluation of a dynamic model using dichloromethane as a model pollutant

    SciTech Connect

    Okkerse, W.J.H.; Osinga-Kuipers, B.; Okkerse, M.; Ottengraf, S.P.P. |

    1999-05-20

    A dynamic model is developed that describes the degradation of volatile acidifying pollutants in biotrickling filters (BTFs) for waste gas purification. Dynamic modelling enables the engineer to predict the clogging rate of a filter bed and the time it takes the BTF to adapt to changes in its inlet concentration. The most important mechanisms that govern the behavior of the BTF are incorporated in the model. The time scale of the accumulation of biomass in a filter is investigated, and an approach is presented that can be used to estimate how long a BTF can be operated before its packing has to be cleaned. A three-month experiment was carried out to validate the model, using dichloromethane (DCM) as a model acidifying pollutant. Valuable experimental data about biomass accumulation and liquid hold-up in the reactor were obtained with an experimental set-up that allows the continuous registration of the weight of the BTF. The results show that in BTFs eliminating DCM from a waste gas, clogging is not to be expected up to concentrations of several g/m{sup 3}. Model calculations based on the measurements also suggest that the maximum carbon load that can safely be applied per unit void packing volume should not exceed 0.5--1.6 C mol/(m{sup 3} {approximately} h), depending on the density of the biofilm formed. The model is a good predictor of the elimination of the pollutant in the system, the axial gas and liquid concentration profiles, the axial biomass distribution, and the response of the system upon a stepwise increase in the DCM inlet concentration. The influence of the buffer concentrations in the liquid phase upon the performance of the BTF is investigated.

  18. LIQUID NATURAL GAS (LNG): AN ALTERNATIVE FUEL FROM LANDFILL GAS (LFG) AND WASTEWATER DIGESTER GAS

    SciTech Connect

    VANDOR,D.

    1999-03-01

    This Research and Development Subcontract sought to find economic, technical and policy links between methane recovery at landfill and wastewater treatment sites in New York and Maryland, and ways to use that methane as an alternative fuel--compressed natural gas (CNG) or liquid natural gas (LNG) -- in centrally fueled Alternative Fueled Vehicles (AFVs).

  19. Impact of physical pre-treatment of source-sorted organic fraction of municipal solid waste on greenhouse-gas emissions and the economy in a Swedish anaerobic digestion system.

    PubMed

    Carlsson, My; Holmström, David; Bohn, Irene; Bisaillon, Mattias; Morgan-Sagastume, Fernando; Lagerkvist, Anders

    2015-04-01

    Several methods for physical pre-treatments of source sorted organic fraction of municipal solid waste (SSOFMSW) before for anaerobic digestion (AD) are available, with the common feature that they generate a homogeneous slurry for AD and a dry refuse fraction for incineration. The selection of efficient methods relies on improved understanding of how the pre-treatment impacts on the separation and on the slurry's AD. The aim of this study was to evaluate the impact of the performance of physical pre-treatment of SSOFMSW on greenhouse-gas (GHG) emissions and on the economy of an AD system including a biogas plant with supplementary systems for heat and power production in Sweden. Based on the performance of selected Swedish facilities, as well as chemical analyses and BMP tests of slurry and refuse, the computer-based evaluation tool ORWARE was improved as to accurately describe mass flows through the physical pre-treatment and anaerobic degradation. The environmental and economic performance of the evaluated system was influenced by the TS concentration in the slurry, as well as the distribution of incoming solids between slurry and refuse. The focus to improve the efficiency of these systems should primarily be directed towards minimising the water addition in the pre-treatment provided that this slurry can still be efficiently digested. Second, the amount of refuse should be minimised, while keeping a good quality of the slurry. Electricity use/generation has high impact on GHG emissions and the results of the study are sensitive to assumptions of marginal electricity and of electricity use in the pre-treatment.

  20. TREATMENT OF HYDROCARBON, ORGANIC RESIDUE AND PRODUCTION CHEMICAL DAMAGE MECHANISMS THROUGH THE APPLICATION OF CARBON DIOXIDE IN NATURAL GAS STORAGE WELLS

    SciTech Connect

    Lawrence J. Pekot

    2004-06-30

    Two gas storage fields were studied for this project. Overisel field, operated by Consumer's Energy, is located near the town of Holland, Michigan. Huntsman Storage Unit, operated by Kinder Morgan, is located in Cheyenne County, Nebraska near the town of Sidney. Wells in both fields experienced declining performance over several years of their annual injection/production cycle. In both fields, the presence of hydrocarbons, organic materials or production chemicals was suspected as the cause of progressive formation damage leading to the performance decline. Core specimens and several material samples were collected from these two natural gas storage reservoirs. Laboratory studies were performed to characterize the samples that were believed to be representative of a reservoir damage mechanism previously identified as arising from the presence of hydrocarbons, organic residues or production chemicals. A series of laboratory experiments were performed to identify the sample materials, use these materials to damage the flow capacity of the core specimens and then attempt to remove or reduce the induced damage using either carbon dioxide or a mixture of carbon dioxide and other chemicals. Results of the experiments showed that pure carbon dioxide was effective in restoring flow capacity to the core specimens in several different settings. However, in settings involving asphaltines as the damage mechanism, both pure carbon dioxide and mixtures of carbon dioxide and other chemicals provided little effectiveness in damage removal.

  1. Gas vesicles.

    PubMed Central

    Walsby, A E

    1994-01-01

    The gas vesicle is a hollow structure made of protein. It usually has the form of a cylindrical tube closed by conical end caps. Gas vesicles occur in five phyla of the Bacteria and two groups of the Archaea, but they are mostly restricted to planktonic microorganisms, in which they provide buoyancy. By regulating their relative gas vesicle content aquatic microbes are able to perform vertical migrations. In slowly growing organisms such movements are made more efficiently than by swimming with flagella. The gas vesicle is impermeable to liquid water, but it is highly permeable to gases and is normally filled with air. It is a rigid structure of low compressibility, but it collapses flat under a certain critical pressure and buoyancy is then lost. Gas vesicles in different organisms vary in width, from 45 to > 200 nm; in accordance with engineering principles the narrower ones are stronger (have higher critical pressures) than wide ones, but they contain less gas space per wall volume and are therefore less efficient at providing buoyancy. A survey of gas-vacuolate cyanobacteria reveals that there has been natural selection for gas vesicles of the maximum width permitted by the pressure encountered in the natural environment, which is mainly determined by cell turgor pressure and water depth. Gas vesicle width is genetically determined, perhaps through the amino acid sequence of one of the constituent proteins. Up to 14 genes have been implicated in gas vesicle production, but so far the products of only two have been shown to be present in the gas vesicle: GvpA makes the ribs that form the structure, and GvpC binds to the outside of the ribs and stiffens the structure against collapse. The evolution of the gas vesicle is discussed in relation to the homologies of these proteins. Images PMID:8177173

  2. Gas magnetometer

    DOEpatents

    Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert

    2016-05-03

    Measurement of a precessional rate of a gas, such as an alkali gas, in a magnetic field is made by promoting a non-uniform precession of the gas in which substantially no net magnetic field affects the gas during a majority of the precession cycle. This allows sensitive gases that would be subject to spin-exchange collision de-phasing to be effectively used for extremely sensitive measurements in the presence of an environmental magnetic field such as the Earth's magnetic field.

  3. Gas chromatography

    NASA Astrophysics Data System (ADS)

    Guiochon, Georges; Guillemin, Claude L.

    1990-11-01

    Gas chromatography is a powerful separation technique for gas and vapor mixtures. Combining separation and on-line detection permits accurate quantitative analysis of complex mixtures, including traces of compounds down to parts per trillions in some particular cases. The importance of gas chromatography in quality control and process control in the chemical and drug industry, in environmental pollution investigations and in clinical analysis is critical. The principles of the technique are discussed, the main components of a gas chromatograph are described and some idea of the importance of the applications is given.

  4. Gas separating

    DOEpatents

    Gollan, A.

    1988-03-29

    Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing. 3 figs.

  5. Gas separating

    DOEpatents

    Gollan, A.Z.

    1990-12-25

    Feed gas is directed tangentially along the non-skin surface of gas separation membrane modules comprising a cylindrical bundle of parallel contiguous hollow fibers supported to allow feed gas to flow from an inlet at one end of a cylindrical housing through the bores of the bundled fibers to an outlet at the other end while a component of the feed gas permeates through the fibers, each having the skin side on the outside, through a permeate outlet in the cylindrical casing. 3 figs.

  6. TREATMENT OF HYDROCARBON, ORGANIC RESIDUE AND PRODUCTION CHEMICAL DAMAGE MECHANISMS THROUGH THE APPLICATION OF CARBON DIOXIDE IN NATURAL GAS STORAGE WELLS

    SciTech Connect

    Lawrence J. Pekot; Ron Himes

    2004-05-31

    Core specimens and several material samples were collected from two natural gas storage reservoirs. Laboratory studies were performed to characterize the samples that were believed to be representative of a reservoir damage mechanism previously identified as arising from the presence of hydrocarbons, organic residues or production chemicals. A series of laboratory experiments were performed to identify the sample materials, use these materials to damage the flow capacity of the core specimens and then attempt to remove or reduce the induced damage using either carbon dioxide or a mixture of carbon dioxide and other chemicals. Results of the experiments showed that pure carbon dioxide was effective in restoring flow capacity to the core specimens in several different settings. However, in settings involving asphaltines as the damage mechanism, both pure carbon dioxide and mixtures of carbon dioxide and other chemicals provided little effectiveness in damage removal.

  7. Occupational arsine gas exposure.

    PubMed

    Pullen-James, Shayla; Woods, Scott E

    2006-12-01

    Arsine gas exposure is a rare occupational event and can be completely prevented with the use of appropriate protective gear. Exposure often occurs when arsine gas is generated while arsenic-containing crude ores or metals are treated with acid. Cases of toxicity require an index of suspicion and a good history. In particular, it should be in the differential diagnosis in patients who present acutely with red/bronze skin and hemoglobinuria. Treatment is supportive and may include transfusions and dialysis in severe cases. Clinical severity is proportionate to the level of exposure, and severity is directly related to the onset of symptoms.

  8. Occupational arsine gas exposure.

    PubMed Central

    Pullen-James, Shayla; Woods, Scott E.

    2006-01-01

    Arsine gas exposure is a rare occupational event and can be completely prevented with the use of appropriate protective gear. Exposure often occurs when arsine gas is generated while arsenic-containing crude ores or metals are treated with acid. Cases of toxicity require an index of suspicion and a good history. In particular, it should be in the differential diagnosis in patients who present acutely with red/bronze skin and hemoglobinuria. Treatment is supportive and may include transfusions and dialysis in severe cases. Clinical severity is proportionate to the level of exposure, and severity is directly related to the onset of symptoms. Images Figure 2 PMID:17225850

  9. Gas Chromatography.

    ERIC Educational Resources Information Center

    Karasek, Francis W.; And Others

    1984-01-01

    This review covers fundamental developments in gas chromatography during 1982 and 1983. Literature is considered under these headings: columns; liguid phases; solid supports; sorption processes and solvents; open tubular column gas chromatography; instrumentation; high-resolution columns and applications; other techniques; qualitative and…

  10. Inflammation-induced drug release by using a pH-responsive gas-generating hollow-microsphere system for the treatment of osteomyelitis.

    PubMed

    Chung, Ming-Fan; Chia, Wei-Tso; Liu, Hung-Yi; Hsiao, Chun-Wen; Hsiao, Hsu-Chan; Yang, Chih-Man; Sung, Hsing-Wen

    2014-11-01

    In the conventional treatment of osteomyelitis, the penetration of antibiotics into the infected bone is commonly poor. To ensure that the local antibiotic concentration is adequate, this work develops an injectable calcium phosphate (CP) cement in which is embedded pH-responsive hollow microspheres (HMs) that can control the release of a drug according to the local pH. The HMs are fabricated using a microfluidic device, with a shell of poly(D,L-lactic-co-glycolic acid) (PLGA) and an aqueous core that contains vancomycin (Van) and NaHCO3. At neutral pH, the CP/HM cement elutes a negligible concentration of the drug. In an acidic environment, the NaHCO3 that is encapsulated in the HMs reacts with the acid rapidly to generate CO2 bubbles, disrupting the PLGA shells and thereby releasing Van locally in excess of a therapeutic threshold. The feasibility of using this CP/HM cement to treat osteomyelitis is studied using a rabbit model. Analytical results reveal that the CP/HM cement provides highly effective local antibacterial activity. Histological examination further verifies the efficacy of the treatment by the CP/HM cement. The above findings suggest that the CP/HM cement is a highly efficient system for the local delivery of antibiotics in the treatment of osteomyelitis.

  11. Number-conserving approach to a minimal self-consistent treatment of condensate and noncondensate dynamics in a degenerate Bose gas

    NASA Astrophysics Data System (ADS)

    Gardiner, S. A.; Morgan, S. A.

    2007-04-01

    We describe a number-conserving approach to the dynamics of Bose-Einstein condensed dilute atomic gases. This builds upon the works of Gardiner [Phys. Rev. A 56, 1414 (1997)] and Castin and Dum [Phys. Rev. A 57, 3008 (1998)]. We consider what is effectively an expansion in powers of the ratio of noncondensate to condensate particle numbers, rather than inverse powers of the total number of particles. This requires the number of condensate particles to be a majority, but not necessarily almost equal to the total number of particles in the system. We argue that a second-order treatment of the relevant dynamical equations of motion is the minimum order necessary to provide consistent coupled condensate and noncondensate number dynamics for a finite total number of particles, and show that such a second-order treatment is provided by a suitably generalized Gross-Pitaevskii equation, coupled to the Castin-Dum number-conserving formulation of the Bogoliubov-de Gennes equations. The necessary equations of motion can be generated from an approximate third-order Hamiltonian, which effectively reduces to second order in the steady state. Such a treatment as described here is suitable for dynamics occurring at finite temperature, where there is a significant noncondensate fraction from the outset, or dynamics leading to dynamical instabilities, where depletion of the condensate can also lead to a significant noncondensate fraction, even if the noncondensate fraction is initially negligible.

  12. Inflammation-induced drug release by using a pH-responsive gas-generating hollow-microsphere system for the treatment of osteomyelitis.

    PubMed

    Chung, Ming-Fan; Chia, Wei-Tso; Liu, Hung-Yi; Hsiao, Chun-Wen; Hsiao, Hsu-Chan; Yang, Chih-Man; Sung, Hsing-Wen

    2014-11-01

    In the conventional treatment of osteomyelitis, the penetration of antibiotics into the infected bone is commonly poor. To ensure that the local antibiotic concentration is adequate, this work develops an injectable calcium phosphate (CP) cement in which is embedded pH-responsive hollow microspheres (HMs) that can control the release of a drug according to the local pH. The HMs are fabricated using a microfluidic device, with a shell of poly(D,L-lactic-co-glycolic acid) (PLGA) and an aqueous core that contains vancomycin (Van) and NaHCO3. At neutral pH, the CP/HM cement elutes a negligible concentration of the drug. In an acidic environment, the NaHCO3 that is encapsulated in the HMs reacts with the acid rapidly to generate CO2 bubbles, disrupting the PLGA shells and thereby releasing Van locally in excess of a therapeutic threshold. The feasibility of using this CP/HM cement to treat osteomyelitis is studied using a rabbit model. Analytical results reveal that the CP/HM cement provides highly effective local antibacterial activity. Histological examination further verifies the efficacy of the treatment by the CP/HM cement. The above findings suggest that the CP/HM cement is a highly efficient system for the local delivery of antibiotics in the treatment of osteomyelitis. PMID:24789379

  13. Effects of Lead and Mercury on Sulfate-Reducing Bacterial Activity in a Biological Process for Flue Gas Desulfurization Wastewater Treatment

    PubMed Central

    Zhang, Liang; Lin, Xiaojuan; Wang, Jinting; Jiang, Feng; Wei, Li; Chen, Guanghao; Hao, Xiaodi

    2016-01-01

    Biological sulfate-reducing bacteria (SRB) may be effective in removing toxic lead and mercury ions (Pb(II) and Hg(II)) from wet flue gas desulfurization (FGD) wastewater through anaerobic sulfite reduction. To confirm this hypothesis, a sulfite-reducing up-flow anaerobic sludge blanket reactor was set up to treat FGD wastewater at metal loading rates of 9.2 g/m3-d Pb(II) and 2.6 g/m3-d Hg(II) for 50 days. The reactor removed 72.5 ± 7% of sulfite and greater than 99.5% of both Hg(II) and Pb(II). Most of the removed lead and mercury were deposited in the sludge as HgS and PbS. The contribution of cell adsorption and organic binding to Pb(II) and Hg(II) removal was 20.0 ± 0.1% and 1.8 ± 1.0%, respectively. The different bioavailable concentration levels of lead and mercury resulted in different levels of lethal toxicity. Cell viability analysis revealed that Hg(II) was less toxic than Pb(II) to the sludge microorganisms. In the batch tests, increasing the Hg(II) feeding concentration increased sulfite reduction rates. In conclusion, a sulfite-reducing reactor can efficiently remove sulfite, Pb(II) and Hg(II) from FGD wastewater. PMID:27455890

  14. The pollutants removal and bacterial community dynamics relationship within a full-scale British Gas/Lurgi coal gasification wastewater treatment using a novel system.

    PubMed

    Jia, Shengyong; Han, Hongjun; Zhuang, Haifeng; Hou, Baolin

    2016-01-01

    The novel system of EBA (based on external circulation anaerobic (EC) process-biological enhanced (BE) process-anoxic/oxic (A/O) process) was applied to treat the British Gas/Lurgi coal gasification wastewater in Erdos, China. After a long time of commissioning, the EBA system represented a stable and highly efficient performance, particularly, the concentrations of COD, NH4(+)-N, total organic carbon, total nitrogen and volatile phenols in the final effluent reached 53, 0.3, 18, 106mg/L and not detected, respectively. Both the GC-MS and fluorescence excitation-emission matrix analyses revealed significant variations of organic compositions in the effluent of different process. The results of high-throughput sequencing represented the EBA system composed 34 main bacteria which were affiliated to 7 phyla. In addition, the canonical correspondence analysis indicated high coherence among community composition, wastewater characteristics and environmental variables, in which the pH, mixed liquid suspended solids and total phenols loading were the most three significant variables. PMID:26476170

  15. A newly isolated Pseudomonas putida S-1 strain for batch-mode-propanethiol degradation and continuous treatment of propanethiol-containing waste gas.

    PubMed

    Chen, Dong-Zhi; Sun, Yi-Ming; Han, Li-Mei; Chen, Jing; Ye, Jie-Xu; Chen, Jian-Meng

    2016-01-25

    Pseudomonas putida S-1 was isolated from activated sludge. This novel strain was capable of degrading malodorous 1-propanethiol (PT). PT degradation commenced with no lag phase by cells pre-grown in nutrition-rich media, such as Luria-Bertani (LB), and PT-contained mineral medium at specific growth rates of 0.10-0.19 h(-1); this phenomenon indicated the operability of a large-scale cell culture. A possible PT degradation pathway was proposed on the basis of the detected metabolites, including dipropyl disulfide, 3-hexanone, 2-hexanone, 3-hexanol, 2-hexanol, S(0), SO4(2-), and CO2. P. putida S-1 could degrade mixed pollutants containing PT, diethyl disulfide, isopropyl alcohol, and acetaldehyde, and LB-pre-cultured cells underwent diauxic growth. Waste gas contaminated with 200-400 mg/m(3) PT was continuously treated by P. putida S-1 pre-cultured in LB medium in a completely stirred tank reactor. The removal efficiencies exceeded 88% when PT stream was mixed with 200 mg/m(3) isopropanol; by contrast, the removal efficiencies decreased to 60% as the empty bed residence time was shortened from 40 s to 20 s. PMID:26476310

  16. Effects of Lead and Mercury on Sulfate-Reducing Bacterial Activity in a Biological Process for Flue Gas Desulfurization Wastewater Treatment.

    PubMed

    Zhang, Liang; Lin, Xiaojuan; Wang, Jinting; Jiang, Feng; Wei, Li; Chen, Guanghao; Hao, Xiaodi

    2016-01-01

    Biological sulfate-reducing bacteria (SRB) may be effective in removing toxic lead and mercury ions (Pb(II) and Hg(II)) from wet flue gas desulfurization (FGD) wastewater through anaerobic sulfite reduction. To confirm this hypothesis, a sulfite-reducing up-flow anaerobic sludge blanket reactor was set up to treat FGD wastewater at metal loading rates of 9.2 g/m(3)-d Pb(II) and 2.6 g/m(3)-d Hg(II) for 50 days. The reactor removed 72.5 ± 7% of sulfite and greater than 99.5% of both Hg(II) and Pb(II). Most of the removed lead and mercury were deposited in the sludge as HgS and PbS. The contribution of cell adsorption and organic binding to Pb(II) and Hg(II) removal was 20.0 ± 0.1% and 1.8 ± 1.0%, respectively. The different bioavailable concentration levels of lead and mercury resulted in different levels of lethal toxicity. Cell viability analysis revealed that Hg(II) was less toxic than Pb(II) to the sludge microorganisms. In the batch tests, increasing the Hg(II) feeding concentration increased sulfite reduction rates. In conclusion, a sulfite-reducing reactor can efficiently remove sulfite, Pb(II) and Hg(II) from FGD wastewater. PMID:27455890

  17. Effects of Lead and Mercury on Sulfate-Reducing Bacterial Activity in a Biological Process for Flue Gas Desulfurization Wastewater Treatment.

    PubMed

    Zhang, Liang; Lin, Xiaojuan; Wang, Jinting; Jiang, Feng; Wei, Li; Chen, Guanghao; Hao, Xiaodi

    2016-01-01

    Biological sulfate-reducing bacteria (SRB) may be effective in removing toxic lead and mercury ions (Pb(II) and Hg(II)) from wet flue gas desulfurization (FGD) wastewater through anaerobic sulfite reduction. To confirm this hypothesis, a sulfite-reducing up-flow anaerobic sludge blanket reactor was set up to treat FGD wastewater at metal loading rates of 9.2 g/m(3)-d Pb(II) and 2.6 g/m(3)-d Hg(II) for 50 days. The reactor removed 72.5 ± 7% of sulfite and greater than 99.5% of both Hg(II) and Pb(II). Most of the removed lead and mercury were deposited in the sludge as HgS and PbS. The contribution of cell adsorption and organic binding to Pb(II) and Hg(II) removal was 20.0 ± 0.1% and 1.8 ± 1.0%, respectively. The different bioavailable concentration levels of lead and mercury resulted in different levels of lethal toxicity. Cell viability analysis revealed that Hg(II) was less toxic than Pb(II) to the sludge microorganisms. In the batch tests, increasing the Hg(II) feeding concentration increased sulfite reduction rates. In conclusion, a sulfite-reducing reactor can efficiently remove sulfite, Pb(II) and Hg(II) from FGD wastewater.

  18. Novel single stripper with side-draw to remove ammonia and sour gas simultaneously for coal-gasification wastewater treatment and the industrial implementation

    SciTech Connect

    Feng, D.C.; Yu, Z.J.; Chen, Y.; Qian, Y.

    2009-06-15

    A large amount of wastewater is produced in the Lurgi coal-gasification process with the complex compounds carbon dioxide, ammonia, phenol, etc., which cause a serious environmental problem. In this paper, a novel stripper operated at elevated pressure is designed to improve the pretreatment process. In this technology, two noticeable improvements were established. First, the carbon dioxide and ammonia were removed simultaneously in a single stripper where sour gas (mainly carbon dioxide) is removed from the tower top and the ammonia vapor is drawn from the side and recovered by partial condensation. Second, the ammonia is removed before the phenol recovery to reduce the pH value of the subsequent extraction units, so as the phenol removal performance of the extraction is greatly improved. To ensure the operational efficiency, some key operational parameters are analyzed and optimized though simulation. It is shown that when the top temperature is kept at 40 C and the weight ratio of the side draw to the feed is above 9%, the elevated pressures can ensure the removal efficiency of NH{sub 3} and carbon dioxide and the desired purified water as the bottom product of the unit is obtained. A real industrial application demonstrates the attractiveness of the new technique: it removes 99.9% CO{sub 2} and 99.6% ammonia, compared to known techniques which remove 66.5% and 94.4%, respectively. As a result, the pH value of the wastewater is reduced from above 9 to below 7. This ensures that the phenol removal ratio is above 93% in the following extraction units. The operating cost is lower than that of known techniques, and the operation is simplified.

  19. Gas Chromatography

    NASA Astrophysics Data System (ADS)

    Hansen, Patrick; Whisnant, C. Steven

    2010-02-01

    To prepare frozen-spin HD targets for photonuclear physics at JLab, high purity HD is required. Commercially available gas is only ˜98% HD. To reach the purity required to make nuclear targets, the gas is distilled at low temperature to remove the H2 and D2 impurities. To monitor the distillation process and correlate the gas purity with the spin relaxation times, a low temperature gas chromatograph system has been developed that produces good separation of H2, HD and D2. The system uses a PLOT 5A column in a mixture of LN2 and i-pentane at temperatures between 110K and 135K. With this system, the relative concentrations can be determined with uncertainties of ˜10%. The chromatography process and the resulting chromatograms will be discussed. )

  20. Volcanic Gas

    MedlinePlus

    ... Hazards Tephra/Ash Lava Flows Lahars Volcanic Gas Climate Change Pyroclastic Flows Volcanic Landslides Preparedness Volcano Hazard Zones ... Please see our discussion of volcanic gases and climate change for additional information. Hydrogen sulfide (H 2 S) is ...

  1. Gas Chromatography.

    ERIC Educational Resources Information Center

    Cram, Stuart P.; And Others

    1980-01-01

    Selects fundamental developments in theory, methodology, and instrumentation in gas chromatography (GC). A special section reviews GC in the People's Republic of China. Over 1,000 references are cited. (CS)

  2. Gas Analyzer

    NASA Astrophysics Data System (ADS)

    1989-01-01

    The M200 originated in the 1970's under an Ames Research Center/Stanford University contract to develop a small, lightweight gas analyzer for Viking Landers. Although the unit was not used on the spacecraft, it was further developed by The National Institute for Occupational Safety and Health (NIOSH). Three researchers from the project later formed Microsensor Technology, Inc. (MTI) to commercialize the analyzer. The original version (Micromonitor 500) was introduced in 1982, and the M200 in 1988. The M200, a more advanced version, features dual gas chromatograph which separate a gaseous mixture into components and measure concentrations of each gas. It is useful for monitoring gas leaks, chemical spills, etc. Many analyses are completed in less than 30 seconds, and a wide range of mixtures can be analyzed.

  3. Heat treatment furnace

    SciTech Connect

    Seals, Roland D; Parrott, Jeffrey G; DeMint, Paul D; Finney, Kevin R; Blue, Charles T

    2014-10-21

    A furnace heats through both infrared radiation and convective air utilizing an infrared/purge gas design that enables improved temperature control to enable more uniform treatment of workpieces. The furnace utilizes lamps, the electrical end connections of which are located in an enclosure outside the furnace chamber, with the lamps extending into the furnace chamber through openings in the wall of the chamber. The enclosure is purged with gas, which gas flows from the enclosure into the furnace chamber via the openings in the wall of the chamber so that the gas flows above and around the lamps and is heated to form a convective mechanism in heating parts.

  4. Solar-chemical treatment of groundwater contaminated with petroleum at gas station sites: ex situ remediation using solar/TiO(2) photocatalysis and Solar Photo-Fenton.

    PubMed

    Cho, Ii-Hyoung; Kim, Young-Gyu; Yang, Jae-Kyu; Lee, Nae-Hyun; Lee, Seung-Mok

    2006-01-01

    Groundwater samples contaminated by BTEX (benzene, toluene, ethylbenzene, xylene isomers and TPHs (total petroleum hydrocarbons) were treated with advanced oxidation processes (AOPs), such as TiO(2) photocatalysis and Fe(2+)/H(2)O(2) exposed to solar light (37 degrees N and 128 degrees E) with an average intensity of 1.7 mW/cm(2) at 365 nm. These AOP processes showed feasibility in the treatment of groundwater contaminated with BTEX, TPH and TOC (Total Organic Carbon). Outdoor field tests showed that the degradation efficiency of each contaminant was higher in the Fe(2+)/H(2)O(2) system without solar light compared to the TiO(2)/solar light and H(2)O(2)/solar light systems. However, the TiO(2)/solar light and the Fe(2+)/H(2)O(2)/solar light systems showed significantly enhanced efficiencies in the degradation of BTEX, TPH and TOC with the additional use of H(2)O(2). Near complete degradation of BTEX and TPH was observed within 2 and 4 hrs, respectively, however, that of TOC was slower. Without pretreatment of the groundwater, fouling of the TiO(2), due to the ionic species present, was observed within 1 hr of operation, which resulted in the inhibition of further BTEX, TPH and TOC destruction. The degradation rate of n-alkanes with carbon numbers ranging from C10 to C15 was relatively greater than that of n-alknaes with carbon numbers ranging from C16 to C20. From this work, the AOP process (Fe(2+)/H(2)O(2)/solar light and TiO(2)/H(2)O(2)/solar light) illuminated with solar light was identified as an effective ex situ technique in the remediation of groundwater contaminated with petroleum.

  5. Gas-fired vacuum technology

    SciTech Connect

    Schultz, T.J.; Bender, J.W.

    2000-04-01

    The modern phase of gas-fired vacuum furnace development began in 1986 under two programs sponsored by the Gas Research Institute . Since then, a tremendous amount of gas industry and private money and time have been spent on the development of this important technology. A key barrier has been the temperature capability of gas-fired designs. Recognizing this, Surface Combustion first began commercial development for low temperature applications and designs. This work resulted in several US patents and ultimately the VacuDraw vacuum tempering furnace. Other commercial configurations and larger sizes subsequently evolved from this successful effort. The most recent development in gas-fired vacuum furnace technology, and perhaps the most significant to date, is the installation and operation of the first multichamber, 1,065 C (1,950 F) system designed for tool steel heat treatment. This article provides an overview of this equipment and describes its key design and performance features.

  6. SST-1 Gas feed and Gas Exhaust system

    NASA Astrophysics Data System (ADS)

    Raval, Dilip C.; Khan, Ziauddin; Thankey, Prashant L.; Dhanani, Kalpesh R.; Pathan, Firozkhan S.; Semwal, Pratibha; George, Siju; Yuvakiran, Paravastu; Manthena, Himabindu; Pradhan, Subrata

    2012-11-01

    SST-1 tokamak is a long pulse tokamak designed for the plasma operation up to 1000 sec duration. Gas feed system and gas exhaust management will play a very crucial role during plasma discharge. During the different type of operations of tokamak like wall conditioning, diverter operation and neutral beam injection, a large amount of gas will be fed into the vacuum chamber at different locations. Also during plasma operations, the gas will be fed both in continues and pulse mode. Gas feed will be carried out mainly using piezo-electric valves controlled by PXI based data acquisition and control system. Such operations will lead to a huge amount gas exhaust by the main system which requires good exhaust facility to searches, great care should be taken in constructing both. Also initial pumping of cryostat and vacuum vessel of SST-1 will release a large amount of gas. Exhausted gases from SST -1 will be Hydrogen, Nitrogen, Mixture gases or some toxic gases. Dedicated exhaust system controlling the different gases are installed. Special treatment of hazardous/explosive gases is done before releasing to the atmosphere. This paper describes design and implementations of the complete gas feed and exhaust system of SST-1.

  7. H. R. 1671: A bill to amend the Internal Revenue Code of 1986 with respect to the treatment of foreign oil and gas income, introduced in the House of Representatives, One Hundred Second Congress, First Session, April 9, 1991

    SciTech Connect

    Not Available

    1991-01-01

    The bill explains special rules for foreign tax credit with respect to foreign oil and gas income by amending the following sections: certain taxes not creditable; separate baskets for foreign oil and gas extraction income and foreign oil related income; and elimination of deferral for foreign oil and gas extraction income. The effective date would be December 31, 1991.

  8. Gas sensor

    DOEpatents

    Schmid, Andreas K.; Mascaraque, Arantzazu; Santos, Benito; de la Figuera, Juan

    2014-09-09

    A gas sensor is described which incorporates a sensor stack comprising a first film layer of a ferromagnetic material, a spacer layer, and a second film layer of the ferromagnetic material. The first film layer is fabricated so that it exhibits a dependence of its magnetic anisotropy direction on the presence of a gas, That is, the orientation of the easy axis of magnetization will flip from out-of-plane to in-plane when the gas to be detected is present in sufficient concentration. By monitoring the change in resistance of the sensor stack when the orientation of the first layer's magnetization changes, and correlating that change with temperature one can determine both the identity and relative concentration of the detected gas. In one embodiment the stack sensor comprises a top ferromagnetic layer two mono layers thick of cobalt deposited upon a spacer layer of ruthenium, which in turn has a second layer of cobalt disposed on its other side, this second cobalt layer in contact with a programmable heater chip.

  9. Cd{sup 2+}/NH{sub 3}-treatment of Cu(In,Ga)(S,Se){sub 2}: Impact on the properties of ZnO layers deposited by the ion layer gas reaction method

    SciTech Connect

    Baer, M.; Bloeck, U.; Muffler, H.-J.; Lux-Steiner, M. C.; Fischer, Ch.-H.; Giersig, M.; Niesen, T.P.; Karg, F.

    2005-01-01

    Cu(In,Ga)(S,Se){sub 2}- (''CIGSSe'') based solar cells with a ZnO layer deposited by the ion layer gas reaction (ILGAR) method yield superior efficiencies (15.0%) than the references with a chemical bath-deposited CdS buffer (14.1%). However, this high performance is only reached if the absorber is pretreated in a Cd{sup 2+}- and aqueous ammonia-containing bath prior to the ILGAR-ZnO deposition. The photovoltaic as well as the dark device parameters are strongly influenced by this treatment. Scanning and transmission electron microscopy (TEM) as well as x-ray diffraction measurements reveal a different morphology and structure of ILGAR-ZnO layers on top of Cd{sup 2+}/NH{sub 3}-treated and on as-deposited absorbers, indicating a considerably modified absorber surface. By energy dispersive x-ray analysis in the TEM, Cd could only be identified at the ILGAR-ZnO/Cd{sup 2+}/NH{sub 3}-treated-CIGSSe interface of the respective cross sections, if the absorber was treated in a bath with an atypically high Cd{sup 2+}-concentration. In this case a Cd-containing thin layer between ZnO and CIGSSe was observed in TEM images.

  10. GAS SEAL

    DOEpatents

    Monson, H.; Hutter, E.

    1961-07-11

    A seal is described for a cover closing an opening in the top of a pressure vessel that may house a nuclear reactor. The seal comprises a U-shaped trough formed on the pressure vessel around the opening therein, a mass of metal in the trough, and an edge flange on the cover extending loosely into the trough and dipping into the metal mass. The lower portion of the metal mass is kept melted, and the upper portion, solid. The solid pontion of the metal mass prevents pressure surges in the vessel from expelling the liquid portion of the metal mass from the trough; the liquld portion, thus held in place by the solid portion, does not allow gas to go through, and so gas cannot escape through shrinkage holes in the solid portion.

  11. Volcanic gas

    USGS Publications Warehouse

    McGee, Kenneth A.; Gerlach, Terrance M.

    1995-01-01

    In Roman mythology, Vulcan, the god of fire, was said to have made tools and weapons for the other gods in his workshop at Olympus. Throughout history, volcanoes have frequently been identified with Vulcan and other mythological figures. Scientists now know that the “smoke" from volcanoes, once attributed by poets to be from Vulcan’s forge, is actually volcanic gas naturally released from both active and many inactive volcanoes. The molten rock, or magma, that lies beneath volcanoes and fuels eruptions, contains abundant gases that are released to the surface before, during, and after eruptions. These gases range from relatively benign low-temperature steam to thick hot clouds of choking sulfurous fume jetting from the earth. Water vapor is typically the most abundant volcanic gas, followed by carbon dioxide and sulfur dioxide. Other volcanic gases are hydrogen sulfide, hydrochloric acid, hydrogen, carbon monoxide, hydrofluoric acid, and other trace gases and volatile metals. The concentrations of these gas species can vary considerably from one volcano to the next.

  12. Gas Plasma Surface Chemistry for Biological Assays.

    PubMed

    Sahagian, Khoren; Larner, Mikki

    2015-01-01

    Biological systems respond to and interact with surfaces. Gas plasma provides a scalable surface treatment method for designing interactive surfaces. There are many commercial examples of plasma-modified products. These include well plates, filtration membranes, dispensing tools, and medical devices. This chapter presents an overview of gas plasma technology and provides a guide to using gas plasma for modifying surfaces for research or product development.

  13. Gas Plasma Surface Chemistry for Biological Assays.

    PubMed

    Sahagian, Khoren; Larner, Mikki

    2015-01-01

    Biological systems respond to and interact with surfaces. Gas plasma provides a scalable surface treatment method for designing interactive surfaces. There are many commercial examples of plasma-modified products. These include well plates, filtration membranes, dispensing tools, and medical devices. This chapter presents an overview of gas plasma technology and provides a guide to using gas plasma for modifying surfaces for research or product development. PMID:26160577

  14. Gas reburning technologies

    SciTech Connect

    Booth, M.

    1996-11-01

    Natural gas reburning technologies are outlined. The following topics are discussed: the reburning process, EER gas reburning experience, gas reburning NOx control overview, Hennepin (tangential) long term test, second generation gas reburning, integrating gas reburning and SNCR, advanced gas reburning process, second generation advanced reburning improvements, and second generation advanced reburning configurations.

  15. Heat treatment effect on crystal structure and design of highly sensitive room temperature CO2 gas sensors using anodic Bi2O3 nanoporous formed in a citric acid electrolyte

    NASA Astrophysics Data System (ADS)

    Ahila, M.; Dhanalakshmi, J.; Celina Selvakumari, J.; Pathinettam Padiyan, D.

    2016-10-01

    The effect of annealing temperature on the crystal structure of anodic bismuth trioxide (ABO) layers prepared via anodization in a citric acid-based electrolyte was studied. The samples were annealed in air at temperatures ranging from 200 °C to 600 °C. Characterization of nanoporous ABO layers was carried out through x-ray diffraction (XRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), UV–visible (UV–Vis) diffuse reflectance spectroscopy and photoluminescence (PL). Effects of heat treatment on crystallinity, morphology and gas-sensing properties were investigated in detail. The XRD measurements showed that a gradual phase change from beta to gamma occurs with an increase in annealing temperature. The beta to gamma transformation occurred between 500 and 600 °C. The changes in the average crystallite sizes of beta and gamma occurring during heat treatment of the ABO layers are correlated with the mechanism of gamma-phase nucleation. During the growth of the gamma phase, the grain size gets enlarged with a reduction in the total area of grain boundary. The pores’ formation and the pore diameter of both anodized and annealed samples were found to be in the range of 50 to 150 nm. The band gap of the ABO layer crystallines was determined using the diffuse reflectance technique according to the Kubelka–Munk theory. Results showed that the band gap of the ABO layer decreased from 4.09 to 2.42 eV when the particle size decreased from 58 to 24 nm. The CO2 sensing properties of the ABO were investigated at room temperature for 0–100 ppm concentration. The variations in the electrical resistances were measured with the exposure of CO2 as a function of time. The maximum value of the response magnitude of 77% was obtained for 100 ppm of CO2. These experimental results show that the ABO layer of nanoporous is a promising material for CO2 sensors at room temperature.

  16. Fuel gas developments

    SciTech Connect

    Wise, D.L.

    1984-01-01

    This volume is devoted to current research and specific developmental programs in the area of fuel gas production from biomass. Anaerobic biological conversion of lignocellulosic residuals to increase methane production by using pretreatment methods such as thermochemical, autohydrolysis, and staged or continuous flow processes are described. Essential considerations for establishing digestion process design criterias are covered. Included in this discussion are the sources and characteristics of municipal solid waste (MSW), MSW preprocessing and pretreatment, and digester control parameters such as nutrient requirements, organic loading rate, retention time, feed slurry concentration, temperature, mixing, and gas quality and quantity. Highlighted are the practical aspects of reactors to promote biomass retention, improving treatment efficiency, product rate, and process stability. Brief summaries are presented on process configuration. Detailed coverage is given to the development and commercialization of anaerobic systems that are now used, such as the Celrobic system and the Biothane process. Problems associated with using biomass digester effluents as soil conditioners and feeds are discussed. The use of commercial manure-to-fuel gas systems at large environmental beef cattle feedlots is also discussed. The volume concludes with a comparative study on the conversion of agricultural crop residues to either gaseous or liquid fuels.

  17. [Gas in the abdominal cavity--due to cholecystitis caused by gas-producing bacteria].

    PubMed

    Miettinen, Simo; Hakkarainen, Timo; Reinikainen, Matti; Hakala, Tapio

    2010-01-01

    In most cases, gas in the abdominal cavity indicates perforation of the gastrointestinal wall. We describe a patient, in whom the cause of abdominal gas detected in computed tomography turned out to be emphysematous cholecystitis caused by gas-producing bacteria. It is a rare disease characterized by accumulation of gas into the gall bladder or its wall. The gas can be easily observed in computed tomography. The disease easily becomes complicated and is associated with high mortality. Prompt cholecystectomy and antibiotic therapy are the cornerstones of the treatment.

  18. Fuel gas conditioning process

    DOEpatents

    Lokhandwala, Kaaeid A.

    2000-01-01

    A process for conditioning natural gas containing C.sub.3+ hydrocarbons and/or acid gas, so that it can be used as combustion fuel to run gas-powered equipment, including compressors, in the gas field or the gas processing plant. Compared with prior art processes, the invention creates lesser quantities of low-pressure gas per unit volume of fuel gas produced. Optionally, the process can also produce an NGL product.

  19. Anaerobic treatment

    SciTech Connect

    Witt, E.R.; Humphrey, W.J.; Cave, J.P.

    1982-12-28

    This invention provides for the anaerobic treatment of acidic petrochemical wastes in an anaerobic filter at high loadings and high recycle rates. The effluent from the top of the filter passes into a gas-disengaging/solids-settling zone containing a quiescent body of the effluent liquid. The settled solids are withdrawn and recycled to the base of the filter together with fresh acidic waste and an inorganic alkaline material (preferably magnesium oxide or carbonate) to maintain a neutral pH. The liquid portion of the effluent is sent to an aerobic digester to remove the rest of the organic material, which is used to support the growth of bacteria and fed back to the anaerobic system.

  20. Incontinence Treatment: Surgical Treatments

    MedlinePlus

    ... Incontinence Managing Incontinence: A Survey The Patient's Perspective Barriers on Diagnosis and Treatment Personal Stories Contact Us ... Incontinence Managing Incontinence: A Survey The Patient's Perspective Barriers on Diagnosis and Treatment Personal Stories Contact Us ...

  1. Intestinal gas dynamics: mechanisms and clinical relevance

    PubMed Central

    Azpiroz, F

    2005-01-01

    Patients with functional gut disorders, irritable bowel disease, and related syndromes frequently attribute their symptoms to intestinal gas. While patients are usually convinced of their interpretation, the doctor has few arguments to confirm or refute it, and in this context intestinal gas has become a myth. Studies of intestinal gas dynamics have demonstrated subtle dysfunctions in intestinal motility. Hopefully, extension of these studies may help both in the classification of patients complaining of gas symptoms based on pathophysiological mechanisms, and in identification of objective markers to test mechanistically oriented treatment options. PMID:15951528

  2. Intestinal gas dynamics: mechanisms and clinical relevance.

    PubMed

    Azpiroz, F

    2005-07-01

    Patients with functional gut disorders, irritable bowel disease, and related syndromes frequently attribute their symptoms to intestinal gas. While patients are usually convinced of their interpretation, the doctor has few arguments to confirm or refute it, and in this context intestinal gas has become a myth. Studies of intestinal gas dynamics have demonstrated subtle dysfunctions in intestinal motility. Hopefully, extension of these studies may help both in the classification of patients complaining of gas symptoms based on pathophysiological mechanisms, and in identification of objective markers to test mechanistically oriented treatment options.

  3. Gas sensing with acoustic devices

    SciTech Connect

    Martin, S.J.; Frye, G.C.; Spates, J.J.; Butler, M.A.

    1996-12-31

    A survey is made of acoustic devices that are suitable as gas and vapor sensors. This survey focuses on attributes such as operating frequency, mass sensitivity, quality factor (Q), and their ability to be fabricated on a semiconductor substrate to allow integration with electronic circuitry. The treatment of the device surface with chemically-sensitive films to detect species of interest is discussed. Strategies for improving discrimination are described, including sensor arrays and species concentration and separation schemes. The advantages and disadvantages of integrating sensors with microelectronics are considered, along with the effect on sensitivity of scaling acoustic gas sensors to smaller size.

  4. Gas Chromatography

    NASA Astrophysics Data System (ADS)

    Qian, Michael C.

    Gas chromatography (GC) has many applications in the analysis of food products. GC has been used for the determination of fatty acids, triglycerides, cholesterol, gases, water, alcohols, pesticides, flavor compounds, and many more. While GC has been used for other food components such as sugars, oligosaccharides, amino acids, peptides, and vitamins, these substances are more suited to analysis by high performance liquid chromatography. GC is ideally suited to the analysis of volatile substances that are thermally stable. Substances such as pesticides and flavor compounds that meet these criteria can be isolated from a food and directly injected into the GC. For compounds that are thermally unstable, too low in volatility, or yield poor chromatographic separation due to polarity, a derivatization step must be done before GC analysis. The two parts of the experiment described here include the analysis of alcohols that requires no derivatization step, and the analysis of fatty acids which requires derivatization. The experiments specify the use of capillary columns, but the first experiment includes conditions for a packed column.

  5. Noble gas fractionation during subsurface gas migration

    NASA Astrophysics Data System (ADS)

    Sathaye, Kiran J.; Larson, Toti E.; Hesse, Marc A.

    2016-09-01

    Environmental monitoring of shale gas production and geological carbon dioxide (CO2) storage requires identification of subsurface gas sources. Noble gases provide a powerful tool to distinguish different sources if the modifications of the gas composition during transport can be accounted for. Despite the recognition of compositional changes due to gas migration in the subsurface, the interpretation of geochemical data relies largely on zero-dimensional mixing and fractionation models. Here we present two-phase flow column experiments that demonstrate these changes. Water containing a dissolved noble gas is displaced by gas comprised of CO2 and argon. We observe a characteristic pattern of initial co-enrichment of noble gases from both phases in banks at the gas front, followed by a depletion of the dissolved noble gas. The enrichment of the co-injected noble gas is due to the dissolution of the more soluble major gas component, while the enrichment of the dissolved noble gas is due to stripping from the groundwater. These processes amount to chromatographic separations that occur during two-phase flow and can be predicted by the theory of gas injection. This theory provides a mechanistic basis for noble gas fractionation during gas migration and improves our ability to identify subsurface gas sources after post-genetic modification. Finally, we show that compositional changes due to two-phase flow can qualitatively explain the spatial compositional trends observed within the Bravo Dome natural CO2 reservoir and some regional compositional trends observed in drinking water wells overlying the Marcellus and Barnett shale regions. In both cases, only the migration of a gas with constant source composition is required, rather than multi-stage mixing and fractionation models previously proposed.

  6. Gas amplified ionization detector for gas chromatography

    DOEpatents

    Huston, Gregg C.

    1992-01-01

    A gas-amplified ionization detector for gas chromatrography which possesses increased sensitivity and a very fast response time. Solutes eluding from a gas chromatographic column are ionized by UV photoionization of matter eluting therefrom. The detector is capable of generating easily measured voltage signals by gas amplification/multiplication of electron products resulting from the UV photoionization of at least a portion of each solute passing through the detector.

  7. Development of a Dual-Fuel Gas Turbine Engine of Liquid and Low-Calorific Gas

    NASA Astrophysics Data System (ADS)

    Koyama, Masamichi; Fujiwara, Hiroshi

    We developed a dual-fuel single can combustor for the Niigata Gas Turbine (NGT2BC), which was developed as a continuous-duty gas turbine capable of burning both kerosene and digester gas. The output of the NGT2BC is 920kW for continuous use with digester gas and 1375kW for emergency use with liquid fuel. Digester gas, obtained from sludge processing at sewage treatment plants, is a biomass energy resource whose use reduces CO2 emissions and take advantage of an otherwise wasted energy source. Design features for good combustion with digester gas include optimized the good matching of gas injection and swirl air and reduced reference velocity. The optimal combination of these parameters was determined through CFD analysis and atmospheric rig testing.

  8. New treatments for keratoconus.

    PubMed

    2011-05-30

    Keratoconus is a fairly common, progressive, noninflammatory, corneal-thinning disorder in which the cornea has a conical shape. Rigid gas permeable (RGP) contact lenses or corneal transplantation are effective treatments, but intracorneal ring segments and collagen cross-linking procedures offer some new alternatives in the management of the disease. PMID:21617595

  9. CONTINUOUS GAS ANALYZER

    DOEpatents

    Katz, S.; Weber, C.W.

    1960-02-16

    A reagent gas and a sample gas are chemically combined on a continuous basis in a reaction zone maintained at a selected temperature. The reagent gas and the sample gas are introduced to the reaction zone at preselected. constant molar rates of flow. The reagent gas and the selected gas in the sample mixture combine in the reaction zone to form a product gas having a different number of moles from the sum of the moles of the reactants. The difference in the total molar rates of flow into and out of the reaction zone is measured and indicated to determine the concentration of the selected gas.

  10. Wastewater treatment plant cogeneration options

    SciTech Connect

    Stringfield, J.G.

    1995-12-31

    This paper reviews municipal sewage cogeneration and digester gas utilization options available to wastewater treatment plants, and will focus on utilizing the digester gas in combustion turbines and engine-generator systems. Defining the digestion and gas generation process is crucial to understanding the best gas utilization system. In municipal wastewater treatment plants biosolids (sludge) reduction is accomplished using aerobic or anaerobic digestion. The basic process of treating sewage solids with digestion is not new and has been practiced as far back as the nineteenth century. High energy usage consumed by aerobic blow systems supplying air to the process and the potential ``free`` energy generated by anaerobic digesters sometimes sways designers to select anaerobic over aerobic digestion. The following areas will be covered in this paper: gas utilization and cogeneration; definition of digestion process; sizing the cogeneration system and reviewing the systems components; emissions requirements and options; and capital, and O and M cost analysis.

  11. Anaesthesia gas supply: gas cylinders.

    PubMed

    Srivastava, Uma

    2013-09-01

    Invention of oxygen cylinder was one of the most important developments in the field of medical practice. Oxygen and other gases were compressed and stored at high pressure in seamless containers constructed from hand-forged steel in1880. Materials technology has continued to evolve and now medical gas cylinders are generally made of steel alloys or aluminum. The filling pressure as well as capacity has increased considerably while at the same time the weight of cylinders has reduced. Today oxygen cylinder of equivalent size holds a third more oxygen but weighs about 20 kg less. The cylinders are of varying sizes and are color coded. They are tested at regular intervals by the manufacturer using hydraulic, impact, and tensile tests. The top end of the cylinder is fitted with a valve with a variety of number and markings stamped on it. Common valve types include: Pin index valve, bull nose, hand wheel and integral valve. The type of valve varies with cylinder size. Small cylinders have a pin index valve while large have a bull nose type. Safety features in the cylinder are: Color coding, pin index, pressure relief device, Bodok seal, and label attached etc., Safety rules and guidelines must be followed during storage, installation and use of cylinders to ensure safety of patients, hospital personnel and the environment.

  12. Anaesthesia Gas Supply: Gas Cylinders

    PubMed Central

    Srivastava, Uma

    2013-01-01

    Invention of oxygen cylinder was one of the most important developments in the field of medical practice. Oxygen and other gases were compressed and stored at high pressure in seamless containers constructed from hand-forged steel in1880. Materials technology has continued to evolve and now medical gas cylinders are generally made of steel alloys or aluminum. The filling pressure as well as capacity has increased considerably while at the same time the weight of cylinders has reduced. Today oxygen cylinder of equivalent size holds a third more oxygen but weighs about 20 kg less. The cylinders are of varying sizes and are color coded. They are tested at regular intervals by the manufacturer using hydraulic, impact, and tensile tests. The top end of the cylinder is fitted with a valve with a variety of number and markings stamped on it. Common valve types include: Pin index valve, bull nose, hand wheel and integral valve. The type of valve varies with cylinder size. Small cylinders have a pin index valve while large have a bull nose type. Safety features in the cylinder are: Color coding, pin index, pressure relief device, Bodok seal, and label attached etc., Safety rules and guidelines must be followed during storage, installation and use of cylinders to ensure safety of patients, hospital personnel and the environment. PMID:24249883

  13. Natural gas production from Arctic gas hydrates

    SciTech Connect

    Collett, T.S. )

    1993-01-01

    The natural gas hydrates of the Messoyakha field in the West Siberian basin of Russia and those of the Prudhoe Bay-Kuparuk River area on the North Slope of Alaska occur within a similar series of interbedded Cretaceous and Tertiary sandstone and siltstone reservoirs. Geochemical analyses of gaseous well-cuttings and production gases suggest that these two hydrate accumulations contain a mixture of thermogenic methane migrated from a deep source and shallow, microbial methane that was either directly converted to gas hydrate or was first concentrated in existing traps and later converted to gas hydrate. Studies of well logs and seismic data have documented a large free-gas accumulation trapped stratigraphically downdip of the gas hydrates in the Prudhoe Bay-Kuparuk River area. The presence of a gas-hydrate/free-gas contact in the Prudhoe Bay-Kuparuk River area is analogous to that in the Messoyakha gas-hydrate/free-gas accumulation, from which approximately 5.17x10[sup 9] cubic meters (183 billion cubic feet) of gas have been produced from the hydrates alone. The apparent geologic similarities between these two accumulations suggest that the gas-hydrated-depressurization production method used in the Messoyakha field may have direct application in northern Alaska. 30 refs., 15 figs., 3 tabs.

  14. Deuterium Gas Analysis by Residual Gas Analyzer

    NASA Astrophysics Data System (ADS)

    Das, B. K.; Shukla, R.; Das, R.; Shyam, A.; Rao, A. D. P.

    2012-11-01

    Hydrogen gas is generated by electrolysis method in a compact hydrogen generator. A simple procedure reduces handling and storage of hydrogen cylinders for laboratory applications. In such a system, we are producing deuterium gas from heavy water by electrolysis method. After production of the deuterium gas, we have checked the purity level of the outgoing deuterium from the electrolyser. The test was carried out in a high vacuum system in which one residual gas analyser (RGA) was mounted. The deuterium gas was inserted by one manual gas leak valve in to the vacuum system. In this study, the effect of the emission current of the RGA on the detection of the deuterium was performed. In this paper, we will discuss the detail analysis of the deuterium gas and the effect of the emission current on the partial pressure measurement.

  15. Delayed onset arterial gas embolism.

    PubMed

    Moloff, A L

    1993-11-01

    Numerous civilian and military personnel are involved in SCUBA diving activities. In this day of rapid air travel it is important that all physicians, not just those living near the coast or dive centers, be familiar with the basics of diagnosing and treating diving-related injuries. One of the more serious complications of dysbarism is Arterial Gas Embolism (AGE). This case history involves an atypical presentation of delayed onset AGE in a military diver trainee, and its treatment. This article then reviews the incidence, etiology, pathophysiology, "classic" presentation and current treatment of this disease. Systemic pathophysiology secondary to the effects of intravascular air of AGE is also discussed.

  16. Computational modeling of intraocular gas dynamics

    NASA Astrophysics Data System (ADS)

    Noohi, P.; Abdekhodaie, M. J.; Cheng, Y. L.

    2015-12-01

    The purpose of this study was to develop a computational model to simulate the dynamics of intraocular gas behavior in pneumatic retinopexy (PR) procedure. The presented model predicted intraocular gas volume at any time and determined the tolerance angle within which a patient can maneuver and still gas completely covers the tear(s). Computational fluid dynamics calculations were conducted to describe PR procedure. The geometrical model was constructed based on the rabbit and human eye dimensions. SF6 in the form of pure and diluted with air was considered as the injected gas. The presented results indicated that the composition of the injected gas affected the gas absorption rate and gas volume. After injection of pure SF6, the bubble expanded to 2.3 times of its initial volume during the first 23 h, but when diluted SF6 was used, no significant expansion was observed. Also, head positioning for the treatment of retinal tear influenced the rate of gas absorption. Moreover, the determined tolerance angle depended on the bubble and tear size. More bubble expansion and smaller retinal tear caused greater tolerance angle. For example, after 23 h, for the tear size of 2 mm the tolerance angle of using pure SF6 is 1.4 times more than that of using diluted SF6 with 80% air. Composition of the injected gas and conditions of the tear in PR may dramatically affect the gas absorption rate and gas volume. Quantifying these effects helps to predict the tolerance angle and improve treatment efficiency.

  17. Computational modeling of intraocular gas dynamics.

    PubMed

    Noohi, P; Abdekhodaie, M J; Cheng, Y L

    2015-12-18

    The purpose of this study was to develop a computational model to simulate the dynamics of intraocular gas behavior in pneumatic retinopexy (PR) procedure. The presented model predicted intraocular gas volume at any time and determined the tolerance angle within which a patient can maneuver and still gas completely covers the tear(s). Computational fluid dynamics calculations were conducted to describe PR procedure. The geometrical model was constructed based on the rabbit and human eye dimensions. SF6 in the form of pure and diluted with air was considered as the injected gas. The presented results indicated that the composition of the injected gas affected the gas absorption rate and gas volume. After injection of pure SF6, the bubble expanded to 2.3 times of its initial volume during the first 23 h, but when diluted SF6 was used, no significant expansion was observed. Also, head positioning for the treatment of retinal tear influenced the rate of gas absorption. Moreover, the determined tolerance angle depended on the bubble and tear size. More bubble expansion and smaller retinal tear caused greater tolerance angle. For example, after 23 h, for the tear size of 2 mm the tolerance angle of using pure SF6 is 1.4 times more than that of using diluted SF6 with 80% air. Composition of the injected gas and conditions of the tear in PR may dramatically affect the gas absorption rate and gas volume. Quantifying these effects helps to predict the tolerance angle and improve treatment efficiency.

  18. Compressed gas manifold

    SciTech Connect

    Hildebrand, Richard J.; Wozniak, John J.

    2001-01-01

    A compressed gas storage cell interconnecting manifold including a thermally activated pressure relief device, a manual safety shut-off valve, and a port for connecting the compressed gas storage cells to a motor vehicle power source and to a refueling adapter. The manifold is mechanically and pneumatically connected to a compressed gas storage cell by a bolt including a gas passage therein.

  19. Noble gas magnetic resonator

    DOEpatents

    Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert

    2014-04-15

    Precise measurements of a precessional rate of noble gas in a magnetic field is obtained by constraining the time averaged direction of the spins of a stimulating alkali gas to lie in a plane transverse to the magnetic field. In this way, the magnetic field of the alkali gas does not provide a net contribution to the precessional rate of the noble gas.

  20. Anyonic quon gas

    NASA Astrophysics Data System (ADS)

    Dalton, Stephen L.; Inomata, Akira

    1995-02-01

    A simple model of a quon gas which exhibits anyonic behavior is proposed. Quons are characterized by the q-mutator, aa † - qa †a = 1 with -1 ≤ q ≤ 1. The gas has the boson and fermion gas limits and can simulate an anyon gas to the second and third virial coefficients.

  1. Natural gas monthly

    SciTech Connect

    1998-01-01

    The Natural Gas Monthly highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer-related activities and underground storage data are also reported. From time to time, the Natural Gas Monthly features articles designed to assist readers in using and interpreting natural gas information.

  2. Decompression sickness and arterial gas embolism in sports scuba divers.

    PubMed

    Gorman, D F

    1989-07-01

    Diving underwater with breathing apparatus is an increasingly popular sport. Consequently, the number of diving-related accidents, including both decompression sickness and arterial gas embolism, have increased. Though both involve bubbles, decompression sickness is a disease which involves gas bubbles forming in tissues and venous blood, while arterial gas embolism results from the introduction of gas bubbles directly into the arterial circulation. Although the pathologies and natural histories of decompression sickness and arterial gas embolism are different, the treatment of these conditions is essentially the same. Compression in a recompression chamber is the definitive treatment of both decompression sickness and arterial gas embolism, and any delay before treatment must be minimised if a good outcome is desired.

  3. Dust filtration in hot coal gas

    SciTech Connect

    Schreurs, H.C.E.

    1995-12-31

    Cleaning up coal gas at high temperatures means a fundamental change to the complete system of an Integrated Coal Gasification Combined Cycle. Coal ash is one of the components that asks for a complete different kind of treating. Several types of dust filtration are available for cleaning up hot coal gas. Several difficulties arise when cleaning up hot coal gas for dust. The paper will deal with the possibilities of the dust cleaning (place, technics), the difficulties (material, efficiencies, residue handling) and the cleaning conditions. It will given an overview of the boundary conditions of dust filtration with respect to slag and ash formation in the gasifier and the coal gas treatment and use after the filtration. Evaluation will show the development path for hot dust filtration, divided into several steps for correct risk analysis. Both former system and feasibility studies on hot gas clean up and ongoing studies and research, all conducted under Novem-assignment, will be reported on.

  4. Integrated production of fuel gas and oxygenated organic compounds from synthesis gas

    DOEpatents

    Moore, Robert B.; Hegarty, William P.; Studer, David W.; Tirados, Edward J.

    1995-01-01

    An oxygenated organic liquid product and a fuel gas are produced from a portion of synthesis gas comprising hydrogen, carbon monoxide, carbon dioxide, and sulfur-containing compounds in a integrated feed treatment and catalytic reaction system. To prevent catalyst poisoning, the sulfur-containing compounds in the reactor feed are absorbed in a liquid comprising the reactor product, and the resulting sulfur-containing liquid is regenerated by stripping with untreated synthesis gas from the reactor. Stripping offgas is combined with the remaining synthesis gas to provide a fuel gas product. A portion of the regenerated liquid is used as makeup to the absorber and the remainder is withdrawn as a liquid product. The method is particularly useful for integration with a combined cycle coal gasification system utilizing a gas turbine for electric power generation.

  5. Cyanide treatment options in coke plants

    SciTech Connect

    Minak, H.P.; Lepke, P.

    1997-12-31

    The paper discusses the formation of cyanides in coke oven gas and describes and compares waste processing options. These include desulfurization by aqueous ammonia solution, desulfurization using potash solution, desulfurization in oxide boxes, decomposition of NH{sub 3} and HCN for gas scrubbing. Waste water treatment methods include chemical oxidation, precipitation, ion exchange, reverse osmosis, and biological treatment. It is concluded that biological treatment is the most economical process, safe in operation and requires a minimum of manpower.

  6. Compressed Gas Safety for Experimental Fusion Facilities

    SciTech Connect

    Cadwallader, L.C.

    2005-05-15

    Experimental fusion facilities present a variety of hazards to the operators and staff. There are unique or specialized hazards, including magnetic fields, cryogens, radio frequency emissions, and vacuum reservoirs. There are also more general industrial hazards, such as a wide variety of electrical power, pressurized air and cooling water systems in use, there are crane and hoist loads, working at height, and handling compressed gas cylinders. This paper outlines the projectile hazard associated with compressed gas cylinders and methods of treatment to provide for compressed gas safety. This information should be of interest to personnel at both magnetic and inertial fusion experiments.

  7. Compressed Gas Safety for Experimental Fusion Facilities

    SciTech Connect

    Lee C. Cadwallader

    2004-09-01

    Experimental fusion facilities present a variety of hazards to the operators and staff. There are unique or specialized hazards, including magnetic fields, cryogens, radio frequency emissions, and vacuum reservoirs. There are also more general industrial hazards, such as a wide variety of electrical power, pressurized air, and cooling water systems in use, there are crane and hoist loads, working at height, and handling compressed gas cylinders. This paper outlines the projectile hazard assoicated with compressed gas cylinders and mthods of treatment to provide for compressed gas safety. This information should be of interest to personnel at both magnetic and inertial fusion experiments.

  8. Resource-assessment perspectives for unconventional gas systems

    USGS Publications Warehouse

    Schmoker, J.W.

    2002-01-01

    Concepts are described for assessing those unconventional gas systems that can also be defined as continous accumulations. Continuous gas accumulations exist more or less independently of the water column and do not owe their existence directly to the bouyancy of gas in water. They cannot be represented in terms of individual, countable fields or pools delineated by downdip water contacts. For these reasons, traditional resource-assessment methods based on estimating the sizes and numbers of undiscovered discrete fields cannot not be applied to continuous accumulations. Specialized assessment methods are required. Unconventional gas systems that are also continous accumulations include coalbed methane, basin-centered gas, so-called tight gas, fractured shale (and chalk) gas, and gas hydrates. Deep-basin and bacterial gas systems may or may not be continuous accumulations, depending on their geologic setting. Two basic resource-assessment approaches have been employed for continous accumulations. The first approach is based on estimates of gas in place. A volumetric estimate of total gas in place is commonly coupled with an overall recovery factor to narrow the assessment scope from a treatment of gas volumes residing in sedimentary strata to a prediction of potential additions to reserves. The second approach is based on the production performance of continous gas reservoirs, as shown empirically by wells and reservoir-simulation models. In these methods, production characteristics (as opposed to gas in place) are the foundation for forecasts of potential additions to reserves.

  9. Hyperbaric treatment

    NASA Technical Reports Server (NTRS)

    Amoroso, Michael T.

    1990-01-01

    Viewgraphs on hyperbaric treatment are presented. Topics covered include: hyperbaric treatment - purpose; decompression sickness; sources of decompression sickness; physical description; forms of decompression sickness; hyperbaric treatment of decompression sickness; and duration of treatment.

  10. Variable leak gas source

    DOEpatents

    Henderson, Timothy M.; Wuttke, Gilbert H.

    1977-01-01

    A variable leak gas source and a method for obtaining the same which includes filling a quantity of hollow glass micro-spheres with a gas, storing said quantity in a confined chamber having a controllable outlet, heating said chamber above room temperature, and controlling the temperature of said chamber to control the quantity of gas passing out of said controllable outlet. Individual gas filled spheres may be utilized for calibration purposes by breaking a sphere having a known quantity of a known gas to calibrate a gas detection apparatus.

  11. Gas-Solid Interactions During Nonisothermal Heat Treatment of a High-Strength CrMnCN Austenitic Steel Powder: Influence of Atmospheric Conditions and Heating Rate on the Densification Behavior

    NASA Astrophysics Data System (ADS)

    Krasokha, Nikolaj; Weber, Sebastian; Huth, Stephan; Zumsande, Kathrin; Theisen, Werner

    2012-11-01

    This work deals with gas-solid interactions between a high-alloyed steel powder and the surrounding atmosphere during continuous heating. It is motivated by the recently developed corrosion-resistant CrMnCN austenitic cast steels. Here, powder metallurgical processing would be desirable to manufacture highly homogeneous parts and/or novel corrosion-resistant metal-matrix composites. However, the successful use of this new production route calls for a comprehensive investigation of interactions between the sintering atmosphere and the metallic powder to prevent undesirable changes to the chemical composition, e.g., degassing of nitrogen or evaporation of manganese. In this study, dilatometric measurements combined with residual gas analysis, high-temperature X-ray diffraction (XRD) measurements, and thermodynamic equilibrium calculations provided detailed information about the influence of different atmospheric conditions on the microstructure, constitution, and densification behavior of a gas-atomized CrMnCN steel powder during continuous heating. Intensive desorption of nitrogen led to the conclusion that a vacuum atmosphere is not suitable for powder metallurgical (PM) processing. Exposure to an N2-containing atmosphere resulted in the formation of nitrides and lattice expansion. Experimental findings have shown that the N content can be controlled by the nitrogen partial pressure. Furthermore, the reduction of surface oxides because of a carbothermal reaction at elevated temperatures and the resulting enhancement of the powder's densification behavior are discussed in this work.

  12. Iran seeking help in regaining prerevolution oil and gas flow

    SciTech Connect

    Tippee, B.

    1996-02-19

    This paper reviews the goals of the Iranian oil and gas industry to rebuild their oil and gas production facilities by using foreign investment. It discusses the historical consequences of war in the region to diminish the production and postpone the recovery of natural gas which is currently flared. It describes the major projects Iran hopes to develop through international partnerships and includes field development, pipeline construction, gas reinjection, gas treatment facilities, and new offshore operation. The paper also reviews the US policy on Iran and its attempt to apply sanctions towards this country.

  13. World Natural Gas Model

    1994-12-01

    RAMSGAS, the Research and Development Analysis Modeling System World Natural Gas Model, was developed to support planning of unconventional gaseoues fuels research and development. The model is a scenario analysis tool that can simulate the penetration of unconventional gas into world markets for oil and gas. Given a set of parameter values, the model estimates the natural gas supply and demand for the world for the period from 1980 to 2030. RAMSGAS is based onmore » a supply/demand framwork and also accounts for the non-renewable nature of gas resources. The model has three fundamental components: a demand module, a wellhead production cost module, and a supply/demand interface module. The demand for gas is a product of total demand for oil and gas in each of 9 demand regions and the gas share. Demand for oil and gas is forecast from the base year of 1980 through 2030 for each demand region, based on energy growth rates and price-induced conservation. For each of 11 conventional and 19 unconventional gas supply regions, wellhead production costs are calculated. To these are added transportation and distribution costs estimates associated with moving gas from the supply region to each of the demand regions and any economic rents. Based on a weighted average of these costs and the world price of oil, fuel shares for gas and oil are computed for each demand region. The gas demand is the gas fuel share multiplied by the total demand for oil plus gas. This demand is then met from the available supply regions in inverse proportion to the cost of gas from each region. The user has almost complete control over the cost estimates for each unconventional gas source in each year and thus can compare contributions from unconventional resources under different cost/price/demand scenarios.« less

  14. Enhanced membrane gas separations

    SciTech Connect

    Prasad, R.

    1993-07-13

    An improved membrane gas separation process is described comprising: (a) passing a feed gas stream to the non-permeate side of a membrane system adapted for the passage of purge gas on the permeate side thereof, and for the passage of the feed gas stream in a counter current flow pattern relative to the flow of purge gas on the permeate side thereof, said membrane system being capable of selectively permeating a fast permeating component from said feed gas, at a feed gas pressure at or above atmospheric pressure; (b) passing purge gas to the permeate side of the membrane system in counter current flow to the flow of said feed gas stream in order to facilitate carrying away of said fast permeating component from the surface of the membrane and maintaining the driving force for removal of the fast permeating component through the membrane from the feed gas stream, said permeate side of the membrane being maintained at a subatmospheric pressure within the range of from about 0.1 to about 5 psia by vacuum pump means; (c) recovering a product gas stream from the non-permeate side of the membrane; and (d) discharging purge gas and the fast permeating component that has permeated the membrane from the permeate side of the membrane, whereby the vacuum conditions maintained on the permeate side of the membrane by said vacuum pump means enhance the efficiency of the gas separation operation, thereby reducing the overall energy requirements thereof.

  15. Natural gas annual 1996

    SciTech Connect

    1997-09-01

    This document provides information on the supply and disposition of natural gas to a wide audience. The 1996 data are presented in a sequence that follows natural gas from it`s production to it`s end use.

  16. Recirculating rotary gas compressor

    DOEpatents

    Weinbrecht, John F.

    1992-01-01

    A positive displacement, recirculating Roots-type rotary gas compressor which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits (24 and 26) which return compressed discharge gas to the compressor housing (14), where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers (10 and 12) and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor.

  17. Microminiature gas chromatograph

    DOEpatents

    Yu, Conrad M.

    1996-01-01

    A microminiature gas chromatograph (.mu.GC) comprising a least one silicon wafer, a gas injector, a column, and a detector. The gas injector has a normally closed valve for introducing a mobile phase including a sample gas in a carrier gas. The valve is fully disposed in the silicon wafer(s). The column is a microcapillary in silicon crystal with a stationary phase and is mechanically connected to receive the mobile phase from the gas injector for the molecular separation of compounds in the sample gas. The detector is mechanically connected to the column for the analysis of the separated compounds of sample gas with electronic means, e.g., ion cell, field emitter and PIN diode.

  18. Recirculating rotary gas compressor

    DOEpatents

    Weinbrecht, J.F.

    1992-02-25

    A positive displacement, recirculating Roots-type rotary gas compressor is described which operates on the basis of flow work compression. The compressor includes a pair of large diameter recirculation conduits which return compressed discharge gas to the compressor housing, where it is mixed with low pressure inlet gas, thereby minimizing adiabatic heating of the gas. The compressor includes a pair of involutely lobed impellers and an associated port configuration which together result in uninterrupted flow of recirculation gas. The large diameter recirculation conduits equalize gas flow velocities within the compressor and minimize gas flow losses. The compressor is particularly suited to applications requiring sustained operation at higher gas compression ratios than have previously been feasible with rotary pumps, and is particularly applicable to refrigeration or other applications requiring condensation of a vapor. 12 figs.

  19. Natural Gas Monthly

    EIA Publications

    2016-01-01

    Highlights activities, events, and analyses associated with the natural gas industry. Volume and price data are presented each month for natural gas production, distribution, consumption, and interstate pipeline activities. Producer related activities and underground storage data are also reported.

  20. Gas gangrene (image)

    MedlinePlus

    Gas gangrene is a severe form of gangrene (tissue death) caused by the bacterium Clostridium perfringens. Patients ... vascular diseases are more prone to spontaneously develop gas gangrene, which is rapidly progressive and often fatal.

  1. Microminiature gas chromatograph

    DOEpatents

    Yu, C.M.

    1996-12-10

    A microminiature gas chromatograph ({mu}GC) comprising a least one silicon wafer, a gas injector, a column, and a detector. The gas injector has a normally closed valve for introducing a mobile phase including a sample gas in a carrier gas. The valve is fully disposed in the silicon wafer(s). The column is a microcapillary in silicon crystal with a stationary phase and is mechanically connected to receive the mobile phase from the gas injector for the molecular separation of compounds in the sample gas. The detector is mechanically connected to the column for the analysis of the separated compounds of sample gas with electronic means, e.g., ion cell, field emitter and PIN diode. 7 figs.

  2. Gas gangrene (image)

    MedlinePlus

    Gas gangrene is a severe form of gangrene (tissue death) caused by the bacterium Clostridium perfringens. It ... causing painful swelling and destruction of involved tissue. Gas gangrene is rapidly progressive and often fatal.

  3. Fiber optic gas sensor

    NASA Technical Reports Server (NTRS)

    Chen, Peng (Inventor); Buric, Michael P. (Inventor); Swinehart, Philip R. (Inventor); Maklad, Mokhtar S. (Inventor)

    2010-01-01

    A gas sensor includes an in-fiber resonant wavelength device provided in a fiber core at a first location. The fiber propagates a sensing light and a power light. A layer of a material is attached to the fiber at the first location. The material is able to absorb the gas at a temperature dependent gas absorption rate. The power light is used to heat the material and increases the gas absorption rate, thereby increasing sensor performance, especially at low temperatures. Further, a method is described of flash heating the gas sensor to absorb more of the gas, allowing the sensor to cool, thereby locking in the gas content of the sensor material, and taking the difference between the starting and ending resonant wavelengths as an indication of the concentration of the gas in the ambient atmosphere.

  4. Fuel gas from biodigestion

    NASA Technical Reports Server (NTRS)

    Mcdonald, R. C.; Wolverton, B. C.

    1979-01-01

    Biodigestion apparatus produces fuel gas (primarily methane) for domestic consumption, by anaerobic bacterial digestion of organic matter such as aquatic vegetation. System includes 3,786-1 cylindrical container, mechanical agitator, and simple safe gas collector for short term storage.

  5. [SURGICAL TREATMENT OF COMPLICATED GASTRODUODENAL ULCER].

    PubMed

    Lupahltsov, V I

    2016-03-01

    Results of operative treatment of 437 patients with complicated gastroduodenal ulcer were summarized. The modern views on the problem of conservative therapy for gas- troduodenal ulcer were presented. A rational individual approach with a certain terms is necessary for conservative treatment of gastroduodenal ulcer. A real way for improve- ment of the patients treatment results--it is a combination of effective conservative treatment with a timely established indications for a planned operative treatment before dangerous complications occur.

  6. [SURGICAL TREATMENT OF COMPLICATED GASTRODUODENAL ULCER].

    PubMed

    Lupahltsov, V I

    2016-03-01

    Results of operative treatment of 437 patients with complicated gastroduodenal ulcer were summarized. The modern views on the problem of conservative therapy for gas- troduodenal ulcer were presented. A rational individual approach with a certain terms is necessary for conservative treatment of gastroduodenal ulcer. A real way for improve- ment of the patients treatment results--it is a combination of effective conservative treatment with a timely established indications for a planned operative treatment before dangerous complications occur. PMID:27514084

  7. Residual gas analysis device

    DOEpatents

    Thornberg, Steven M.

    2012-07-31

    A system is provided for testing the hermeticity of a package, such as a microelectromechanical systems package containing a sealed gas volume, with a sampling device that has the capability to isolate the package and breach the gas seal connected to a pulse valve that can controllably transmit small volumes down to 2 nanoliters to a gas chamber for analysis using gas chromatography/mass spectroscopy diagnostics.

  8. Liquid propellant gas generators

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The design of gas generators intended to provide hot gases for turbine drive is discussed. Emphasis is placed on the design and operation of bipropellant gas generators because of their wider use. Problems and limitations involved in turbine operation due to temperature effects are analyzed. Methods of temperature control of gas turbines and combustion products are examined. Drawings of critical sections of gas turbines to show their operation and areas of stress are included.

  9. Natural gas annual 1994

    SciTech Connect

    1995-11-17

    The Natural Gas Annual provides information on the supply and disposition of natural gas to a wide audience including industry, consumers, Federal and State agencies, and educational institutions. The 1994 data are presented in a sequence that follows natural gas (including supplemental supplies) from its production to its end use. This is followed by tables summarizing natural gas supply and disposition from 1990 to 1994 for each Census Division and each State. Annual historical data are shown at the national level.

  10. Natural gas annual 1995

    SciTech Connect

    1996-11-01

    The Natural Gas Annual provides information on the supply and disposition of natural gas to a wide audience including industry, consumers, Federal and State agencies, and educational institutions. The 1995 data are presented in a sequence that follows natural gas (including supplemental supplies) from its production to its end use. This is followed by tables summarizing natural gas supply and disposition from 1991 to 1995 for each Census Division and each State. Annual historical data are shown at the national level.

  11. Microscale Gas Chemistry

    ERIC Educational Resources Information Center

    Mattson, Bruce; Anderson, Michael P.

    2011-01-01

    The development of syringes having free movement while remaining gas-tight enabled methods in chemistry to be changed. Successfully containing and measuring volumes of gas without the need to trap them using liquids made it possible to work with smaller quantities. The invention of the LuerLok syringe cap also allowed the gas to be stored for a…

  12. Geopolitics of natural gas

    SciTech Connect

    Russell, J.

    1983-01-01

    This examines the role of gas in the world energy supply/demand. Special attention is paid to Western Europe, the Soviet Union, and the natural gas exporting countries. Forecasts of global energy demand until 2000 and data on Western Europe's proven natural gas reserves as per January 1982 are provided.

  13. Demonstrating the Gas Laws.

    ERIC Educational Resources Information Center

    Holko, David A.

    1982-01-01

    Presents a complete computer program demonstrating the relationship between volume/pressure for Boyle's Law, volume/temperature for Charles' Law, and volume/moles of gas for Avagadro's Law. The programing reinforces students' application of gas laws and equates a simulated moving piston to theoretical values derived using the ideal gas law.…

  14. Static gas expansion cooler

    DOEpatents

    Guzek, J.C.; Lujan, R.A.

    1984-01-01

    Disclosed is a cooler for television cameras and other temperature sensitive equipment. The cooler uses compressed gas ehich is accelerated to a high velocity by passing it through flow passageways having nozzle portions which expand the gas. This acceleration and expansion causes the gas to undergo a decrease in temperature thereby cooling the cooler body and adjacent temperature sensitive equipment.

  15. Valve for gas centrifuges

    DOEpatents

    Hahs, C.A.; Rurbage, C.H.

    1982-03-17

    The invention is pneumatically operated valve assembly for simulatenously (1) closing gas-transfer lines connected to a gas centrifuge or the like and (2) establishing a recycle path between two on the lines so closed. The value assembly is especially designed to be compact, fast-acting, reliable, and comparatively inexpensive. It provides large reductions in capital costs for gas-centrifuge cascades.

  16. Gas dynamics in residual gas analyzer calibration

    SciTech Connect

    Santeler, D.J.

    1987-01-01

    Residual gas analyzers are used for measuring partial flow rates as well as for measuring partial pressures. The required calibration may also be obtained with either known flow rates or known pressures. The calibration and application procedures are straightforward when both are of the same type; however, substantial errors may occur if the two types are mixed. This report develops the basic equations required to convert between partial pressure calibrations and partial flow rate calibrations. It also discusses the question of fractionating and nonfractionating gas flow in various gas inlet and pumping systems.

  17. Radon gas distribution in natural gas processing facilities and workplace air environment.

    PubMed

    Al-Masri, M S; Shwiekani, R

    2008-04-01

    Evaluation was made of the distribution of radon gas and radiation exposure rates in the four main natural gas treatment facilities in Syria. The results showed that radiation exposure rates at contact of all equipment were within the natural levels (0.09-0.1 microSvh(-1)) except for the reflex pumps where a dose rate value of 3 microSvh(-1) was recorded. Radon concentrations in Syrian natural gas varied between 15.4 Bq m(-3) and 1141 Bq m(-3); natural gas associated with oil production was found to contain higher concentrations than the non-associated natural gas. In addition, radon concentrations were higher in the central processing facilities than the wellheads; these high levels are due to pressurizing and concentrating processes that enhance radon gas and its decay products. Moreover, the lowest 222Rn concentration was in the natural gas fraction used for producing sulfur; a value of 80 Bq m(-3) was observed. On the other hand, maximum radon gas and its decay product concentrations in workplace air environments were found to be relatively high in the gas analysis laboratories; a value of 458 Bq m(-3) was observed. However, all reported levels in the workplaces in the four main stations were below the action level set by IAEA for chronic exposure situations involving radon, which is 1000 Bq m(-3). PMID:17905489

  18. Radon gas distribution in natural gas processing facilities and workplace air environment.

    PubMed

    Al-Masri, M S; Shwiekani, R

    2008-04-01

    Evaluation was made of the distribution of radon gas and radiation exposure rates in the four main natural gas treatment facilities in Syria. The results showed that radiation exposure rates at contact of all equipment were within the natural levels (0.09-0.1 microSvh(-1)) except for the reflex pumps where a dose rate value of 3 microSvh(-1) was recorded. Radon concentrations in Syrian natural gas varied between 15.4 Bq m(-3) and 1141 Bq m(-3); natural gas associated with oil production was found to contain higher concentrations than the non-associated natural gas. In addition, radon concentrations were higher in the central processing facilities than the wellheads; these high levels are due to pressurizing and concentrating processes that enhance radon gas and its decay products. Moreover, the lowest 222Rn concentration was in the natural gas fraction used for producing sulfur; a value of 80 Bq m(-3) was observed. On the other hand, maximum radon gas and its decay product concentrations in workplace air environments were found to be relatively high in the gas analysis laboratories; a value of 458 Bq m(-3) was observed. However, all reported levels in the workplaces in the four main stations were below the action level set by IAEA for chronic exposure situations involving radon, which is 1000 Bq m(-3).

  19. Solid-phase extraction-gas chromatography and solid-phase extraction-gas chromatography-mass spectrometry determination of corrosion inhibiting long-chain primary alkyl amines in chemical treatment of boiler water in water-steam systems of power plants.

    PubMed

    Kusch, Peter; Knupp, Gerd; Hergarten, Marcus; Kozupa, Marian; Majchrzak, Maria

    2006-04-28

    Gas chromatography with simultaneous flame-ionization detection (FID) and a nitrogen-phosphorus detection (NPD) as well as gas chromatography-mass spectrometry (GC/MS) has been used to characterize long-chain primary alkyl amines after derivatization with trifluoroacetic anhydride (TFAA). Electron impact ionization- (EI) and negative chemical ionization (NCI) mass spectra of trifluoroacetylated derivatives of the identified tert-octadecylamines are presented for the first time. The corrosion inhibiting alkyl amines were applied in a water-steam circuit of energy systems in the power industry. Solid-phase extraction (SPE) with octadecyl bonded silica (C18) sorbents followed by gas chromatography were used for quantification of the investigated tert-octadecylamines in boiler water, superheated steam and condensate samples from the power plant. The estimated values were: 89 microg l(-1)(n = 5, RSD = 7.8%), 45 microg l(-1) (n = 5, RSD = 5.4%) and 37 microg l(-1)(n = 5, RSD = 2.3%), respectively.

  20. Solid-phase extraction-gas chromatography and solid-phase extraction-gas chromatography-mass spectrometry determination of corrosion inhibiting long-chain primary alkyl amines in chemical treatment of boiler water in water-steam systems of power plants.

    PubMed

    Kusch, Peter; Knupp, Gerd; Hergarten, Marcus; Kozupa, Marian; Majchrzak, Maria

    2006-04-28

    Gas chromatography with simultaneous flame-ionization detection (FID) and a nitrogen-phosphorus detection (NPD) as well as gas chromatography-mass spectrometry (GC/MS) has been used to characterize long-chain primary alkyl amines after derivatization with trifluoroacetic anhydride (TFAA). Electron impact ionization- (EI) and negative chemical ionization (NCI) mass spectra of trifluoroacetylated derivatives of the identified tert-octadecylamines are presented for the first time. The corrosion inhibiting alkyl amines were applied in a water-steam circuit of energy systems in the power industry. Solid-phase extraction (SPE) with octadecyl bonded silica (C18) sorbents followed by gas chromatography were used for quantification of the investigated tert-octadecylamines in boiler water, superheated steam and condensate samples from the power plant. The estimated values were: 89 microg l(-1)(n = 5, RSD = 7.8%), 45 microg l(-1) (n = 5, RSD = 5.4%) and 37 microg l(-1)(n = 5, RSD = 2.3%), respectively. PMID:16483586

  1. Experimental Characterization of Gas/Gas Injector Flowfields

    NASA Technical Reports Server (NTRS)

    Marshall, William M.; Cramer, John M.; Pal, Sibtosh; Santoro, Robert J.; Turner, Jim (Technical Monitor)

    2002-01-01

    This viewgraph presentation provides information on activities pertaining to the experimental characterization of gas/gas injector flowfields. An experimental testbed for uni-element gas/gas injector studies at realistic conditions has been fabricated and verified. Experiments for characterizing mixing/combustion of gas/gas injectors with raman spectroscopy have been initiated.

  2. Flue gas desulfurization

    DOEpatents

    Im, Kwan H.; Ahluwalia, Rajesh K.

    1985-01-01

    A process and apparatus for removing sulfur oxide from combustion gas to form Na.sub.2 SO.sub.4 and for reducing the harmful effects of Na.sub.2 SO.sub.4 on auxiliary heat exchangers in which a sodium compound is injected into the hot combustion gas forming liquid Na.sub.2 SO.sub.4 in a gas-gas reaction and the resultant gas containing Na.sub.2 SO.sub.4 is cooled to below about 1150.degree. K. to form particles of Na.sub.2 SO.sub.4 prior to contact with at least one heat exchanger with the cooling being provided by the recycling of combustion gas from a cooled zone downstream from the introduction of the cooling gas.

  3. Natural gas leak mapper

    DOEpatents

    Reichardt, Thomas A.; Luong, Amy Khai; Kulp, Thomas J.; Devdas, Sanjay

    2008-05-20

    A system is described that is suitable for use in determining the location of leaks of gases having a background concentration. The system is a point-wise backscatter absorption gas measurement system that measures absorption and distance to each point of an image. The absorption measurement provides an indication of the total amount of a gas of interest, and the distance provides an estimate of the background concentration of gas. The distance is measured from the time-of-flight of laser pulse that is generated along with the absorption measurement light. The measurements are formated into an image of the presence of gas in excess of the background. Alternatively, an image of the scene is superimosed on the image of the gas to aid in locating leaks. By further modeling excess gas as a plume having a known concentration profile, the present system provides an estimate of the maximum concentration of the gas of interest.

  4. Gas Hydrate Storage of Natural Gas

    SciTech Connect

    Rudy Rogers; John Etheridge

    2006-03-31

    Environmental and economic benefits could accrue from a safe, above-ground, natural-gas storage process allowing electric power plants to utilize natural gas for peak load demands; numerous other applications of a gas storage process exist. A laboratory study conducted in 1999 to determine the feasibility of a gas-hydrates storage process looked promising. The subsequent scale-up of the process was designed to preserve important features of the laboratory apparatus: (1) symmetry of hydrate accumulation, (2) favorable surface area to volume ratio, (3) heat exchanger surfaces serving as hydrate adsorption surfaces, (4) refrigeration system to remove heat liberated from bulk hydrate formation, (5) rapid hydrate formation in a non-stirred system, (6) hydrate self-packing, and (7) heat-exchanger/adsorption plates serving dual purposes to add or extract energy for hydrate formation or decomposition. The hydrate formation/storage/decomposition Proof-of-Concept (POC) pressure vessel and supporting equipment were designed, constructed, and tested. This final report details the design of the scaled POC gas-hydrate storage process, some comments on its fabrication and installation, checkout of the equipment, procedures for conducting the experimental tests, and the test results. The design, construction, and installation of the equipment were on budget target, as was the tests that were subsequently conducted. The budget proposed was met. The primary goal of storing 5000-scf of natural gas in the gas hydrates was exceeded in the final test, as 5289-scf of gas storage was achieved in 54.33 hours. After this 54.33-hour period, as pressure in the formation vessel declined, additional gas went into the hydrates until equilibrium pressure/temperature was reached, so that ultimately more than the 5289-scf storage was achieved. The time required to store the 5000-scf (48.1 hours of operating time) was longer than designed. The lower gas hydrate formation rate is attributed to a

  5. NITROGEN REMOVAL FROM NATURAL GAS

    SciTech Connect

    K.A. Lokhandwala; M.B. Ringer; T.T. Su; Z. He; I. Pinnau; J.G. Wijmans; A. Morisato; K. Amo; A. DaCosta; R.W. Baker; R. Olsen; H. Hassani; T. Rathkamp

    1999-12-31

    The objective of this project was to develop a membrane process for the denitrogenation of natural gas. Large proven reserves in the Lower-48 states cannot be produced because of the presence of nitrogen. To exploit these reserves, cost-effective, simple technology able to reduce the nitrogen content of the gas to 4-5% is required. Technology applicable to treatment of small gas streams (below 10 MMscfd) is particularly needed. In this project membranes that selectively permeate methane and reject nitrogen in the gas were developed. Preliminary calculations show that a membrane with a methane/nitrogen selectivity of 3 to 5 is required to make the process economically viable. A number of polymer materials likely to have the required selectivities were evaluated as composite membranes. Polyacetylenes such as poly(1-trimethylsilyl-1-propyne) [PTMSP] and poly(4-methyl-2-pentyne) [PMP] had high selectivities and fluxes, but membranes prepared from these polymers were not stable, showing decreasing flux and selectivity during tests lasting only a few hours. Parel, a poly(propylene oxide allyl glycidyl ether) had a selectivity of 3 at ambient temperatures and 4 or more at temperatures of {minus}20 C. However, Parel is no longer commercially available, and we were unable to find an equivalent material in the time available. Therefore, most of our experimental work focused on silicone rubber membranes, which have a selectivity of 2.5 at ambient temperatures, increasing to 3-4 at low temperatures. Silicone rubber composite membranes were evaluated in bench-scale module tests and with commercial-scale, 4-inch-diameter modules in a small pilot plant. Over six days of continuous operation at a feed gas temperature of {minus}5 to {minus}10 C, the membrane maintained a methane/nitrogen selectivity of about 3.3. Based on the pilot plant performance data, an analysis of the economic potential of the process was prepared. We conclude that a stand-alone membrane process is the lowest

  6. Revamping AK-Ashland gas cleaning system

    SciTech Connect

    Brandes, H.; Koerbel, R.; Haberkamp, K.; Keeton, S.

    1995-07-01

    AK Steel`s (formerly Armco) BOF shop was using a static precipitator for the primary collection. The system was designed for full combustion in the gas collecting hoods. No secondary dust collection was in place. A detailed study on alternative solutions led to a completely different system in 1990, and an order was awarded to Mannesmann Demag Corp. (MDC) in Dec. 1990. The new gas collection system is using suppressed combustion with the capability to collect Co at a later stage. The gas cleaning uses the Mannesmann Demag Baumco scrubber with a venturi throat for gas flow control. All auxiliary components, water treatment plant, electric substations and sludge handling were designed and supplied by MDC. The secondary dust collection covers the hot metal and scrap charging into the BOF`s, reladling, desulfurization and deslagging by a pulse jet baghouse. All emission limits set by the EPA and guaranteed by MDC have been met by the systems installed.

  7. The structure of hydrophobic gas diffusion electrodes.

    NASA Technical Reports Server (NTRS)

    Giner, J.

    1972-01-01

    The 'flooded agglomerate' model of the Teflon-bonded gas diffusion electrode is discussed. A mathematical treatment of the 'flooded agglomerate' model is given; it can be used to predict the performance of the electrode as a function of measurable physical parameters.

  8. SOIL GAS OXYGEN TENSION AND PENTACHLOROPHENOL BIODEGRADATION

    EPA Science Inventory

    Laboratory tests were conducted to determine the effect of soil gas oxygen concentration on the degradation and mineralization of spiked 14C-pentachlorophenol and nonlabeled pentachlorophenol (PCP) present in soil taken from a prepared-bed land treatment unit at the Champion Inte...

  9. Radon gas, useful for medical purposes, safely fixed in quartz

    NASA Technical Reports Server (NTRS)

    Fields, P. R.; Stein, L.; Zirin, M. H.

    1966-01-01

    Radon gas is enclosed in quartz or glass ampules by subjecting the gas sealed at a low pressure in the ampules to an ionization process. This process is useful for preparing fixed radon sources for radiological treatment of malignancies, without the danger of releasing radioactive gases.

  10. Scaling in electron scattering from a relativistic Fermi gas

    SciTech Connect

    W. M. Alberico; A. Molinari; T. William Donnelly; E. L. Kronenberg; Wally Van Orden

    1988-10-01

    Within the context of the relativistic Fermi gas model, the concept of ''y scaling'' for inclusive electron scattering from nuclei is investigated. Specific kinematic shifts of the single-nucleon response in the nuclear medium can be incorporated with this model. Suggested generalizations beyond the strict Fermi gas model, including treatments of separated longitudinal and transverse responses, are also explored.

  11. Economic evaluation of fiberglass tubing in gas well service

    SciTech Connect

    Bass, G.N.; Maddux, G.C. )

    1991-03-01

    This paper reports that corrosion-induced problems have caused failures in many oil and gas investments. Corrosion inhibitor treatments do not always provide corrosion protection needed for optimum production and return of investment. Several economic considerations are presented with a case history of using fiberglass tubulars in high-water rate flowing gas well service.

  12. Shale gas development impacts on surface water quality in Pennsylvania

    PubMed Central

    Olmstead, Sheila M.; Muehlenbachs, Lucija A.; Shih, Jhih-Shyang; Chu, Ziyan; Krupnick, Alan J.

    2013-01-01

    Concern has been raised in the scientific literature about the environmental implications of extracting natural gas from deep shale formations, and published studies suggest that shale gas development may affect local groundwater quality. The potential for surface water quality degradation has been discussed in prior work, although no empirical analysis of this issue has been published. The potential for large-scale surface water quality degradation has affected regulatory approaches to shale gas development in some US states, despite the dearth of evidence. This paper conducts a large-scale examination of the extent to which shale gas development activities affect surface water quality. Focusing on the Marcellus Shale in Pennsylvania, we estimate the effect of shale gas wells and the release of treated shale gas waste by permitted treatment facilities on observed downstream concentrations of chloride (Cl−) and total suspended solids (TSS), controlling for other factors. Results suggest that (i) the treatment of shale gas waste by treatment plants in a watershed raises downstream Cl− concentrations but not TSS concentrations, and (ii) the presence of shale gas wells in a watershed raises downstream TSS concentrations but not Cl− concentrations. These results can inform future voluntary measures taken by shale gas operators and policy approaches taken by regulators to protect surface water quality as the scale of this economically important activity increases. PMID:23479604

  13. Shale gas development impacts on surface water quality in Pennsylvania.

    PubMed

    Olmstead, Sheila M; Muehlenbachs, Lucija A; Shih, Jhih-Shyang; Chu, Ziyan; Krupnick, Alan J

    2013-03-26

    Concern has been raised in the scientific literature about the environmental implications of extracting natural gas from deep shale formations, and published studies suggest that shale gas development may affect local groundwater quality. The potential for surface water quality degradation has been discussed in prior work, although no empirical analysis of this issue has been published. The potential for large-scale surface water quality degradation has affected regulatory approaches to shale gas development in some US states, despite the dearth of evidence. This paper conducts a large-scale examination of the extent to which shale gas development activities affect surface water quality. Focusing on the Marcellus Shale in Pennsylvania, we estimate the effect of shale gas wells and the release of treated shale gas waste by permitted treatment facilities on observed downstream concentrations of chloride (Cl(-)) and total suspended solids (TSS), controlling for other factors. Results suggest that (i) the treatment of shale gas waste by treatment plants in a watershed raises downstream Cl(-) concentrations but not TSS concentrations, and (ii) the presence of shale gas wells in a watershed raises downstream TSS concentrations but not Cl(-) concentrations. These results can inform future voluntary measures taken by shale gas operators and policy approaches taken by regulators to protect surface water quality as the scale of this economically important activity increases.

  14. Effect of Post-Weld Heat Treatment on Mechanical and Electrochemical Properties of Gas Metal Arc-Welded 316L (X2CrNiMo 17-13-2) Stainless Steel

    NASA Astrophysics Data System (ADS)

    Muhammad, F.; Ahmad, A.; Farooq, A.; Haider, W.

    2016-08-01

    In the present research work, corrosion behavior of post-weld heat-treated (PWHT) AISI 316L (X2CrNiMo 17-13-2) specimens joined by gas metal arc welding is compared with as-welded samples by using potentiodynamic polarization technique. Welded samples were PWHT at 1323 K for 480 s and quenched. Mechanical properties, corrosion behavior and microstructures of as-welded and PWHT specimens were investigated. Microstructural studies have shown grain size refinement after PWHT. Ultimate tensile strength and yield strength were found maximum for PWHT samples. Bend test have shown that PWHT imparted ductility in welded sample. Fractographic analysis has evidenced ductile behavior for samples. Potentiodynamic polarization test was carried out in a solution composed of 1 M H2SO4 and 1 N NaCl. Corrosion rate of weld region was 127.6 mpy, but after PWHT, it was decreased to 13.12 mpy.

  15. Effect of Post-Weld Heat Treatment on Mechanical and Electrochemical Properties of Gas Metal Arc-Welded 316L (X2CrNiMo 17-13-2) Stainless Steel

    NASA Astrophysics Data System (ADS)

    Muhammad, F.; Ahmad, A.; Farooq, A.; Haider, W.

    2016-10-01

    In the present research work, corrosion behavior of post-weld heat-treated (PWHT) AISI 316L (X2CrNiMo 17-13-2) specimens joined by gas metal arc welding is compared with as-welded samples by using potentiodynamic polarization technique. Welded samples were PWHT at 1323 K for 480 s and quenched. Mechanical properties, corrosion behavior and microstructures of as-welded and PWHT specimens were investigated. Microstructural studies have shown grain size refinement after PWHT. Ultimate tensile strength and yield strength were found maximum for PWHT samples. Bend test have shown that PWHT imparted ductility in welded sample. Fractographic analysis has evidenced ductile behavior for samples. Potentiodynamic polarization test was carried out in a solution composed of 1 M H2SO4 and 1 N NaCl. Corrosion rate of weld region was 127.6 mpy, but after PWHT, it was decreased to 13.12 mpy.

  16. Flue gas desulfurization

    DOEpatents

    Im, K.H.; Ahluwalia, R.K.

    1984-05-01

    The invention involves a combustion process in which combustion gas containing sulfur oxide is directed past a series of heat exchangers to a stack and in which a sodium compound is added to the combustion gas in a temparature zone of above about 1400 K to form Na/sub 2/SO/sub 4/. Preferably, the temperature is above about 1800 K and the sodium compound is present as a vapor to provide a gas-gas reaction to form Na/sub 2/SO/sub 4/ as a liquid. Since liquid Na/sub 2/SO/sub 4/ may cause fouling of heat exchanger surfaces downstream from the combustion zone, the process advantageously includes the step of injecting a cooling gas downstream of the injection of the sodium compound yet upstream of one or more heat exchangers to cool the combustion gas to below about 1150 K and form solid Na/sub 2/SO/sub 4/. The cooling gas is preferably a portion of the combustion gas downstream which may be recycled for cooling. It is further advantageous to utilize an electrostatic precipitator downstream of the heat exchangers to recover the Na/sub 2/SO/sub 4/. It is also advantageous in the process to remove a portion of the combustion gas cleaned in the electrostatic precipitator and recycle that portion upstream to use as the cooling gas. 3 figures.

  17. 2. SALEMBROSIUS CONTINUOUS GASFIRED HEAT TREATING LINE AT HEAT TREATMENT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. SALEM-BROSIUS CONTINUOUS GAS-FIRED HEAT TREATING LINE AT HEAT TREATMENT PLANT OF THE DUQUESNE WORKS. - U.S. Steel Duquesne Works, Heat Treatment Plant, Along Monongahela River, Duquesne, Allegheny County, PA

  18. Gas dynamics and Stirling engines

    SciTech Connect

    Organ, A.J.

    1995-12-31

    The Method of Characteristics is adapted for computer solution of pulsatile flow in the presence of flow area discontinuities. The treatment is applied to the Stirling engine gas circuit. Compressibility effects show up clearly at a Mach number, u/a, of 0.01 -- i.e. at one thirtieth of the 0.3 or so used by convention as the demarcation between incompressible and compressible flow. Indeed, it is demonstrated that there is no lower limit to the Mach number at which the effects of compressibility can be quantified. The treatment paves the way for comprehensive simulation of the Stirling machine taking into account the complex geometry of the regenerator packing.

  19. Combined biological and physicochemical waste-gas cleaning techniques.

    PubMed

    Rene, Eldon R; Veiga, María C; Kennes, Christian

    2012-01-01

    This review presents a general overview of physical, chemical and biological waste-gas treatment techniques such as adsorption, absorption, oxidation and biodegradation, focusing more extensively on combined processes. It is widely recognized that biological waste-gas treatment devices such as biofilters and biotrickling filters can show high performance, often reaching removal efficiencies above 90 % for pollutant concentrations below 5 g/m(3). However, for concentrations exceeding this limit and under transient shock-load conditions that are frequently encountered in industrial situations, a physicochemical gas cleaning process can sometimes be advantageously combined with a biological one. Besides improving the overall treatment efficiency, the non-biological, first-stage process could also serve as a load equalization system by reducing the pollutant load during periodic shock-loads, to levels that can easily be handled in the second-stage bioreactor. This article reviews the operational advantages of integrating different non-biological and biological processes, i.e., adsorption pre-treatment+bioreactor, bioreactor+adsorption post-treatment, absorption pre-treatment+bioreactor, UV pre-treatment+bioreactor, and bioreactor/bioreactor combinations, for waste-gas treatment, where different gas-phase pollutants have been tested.

  20. 78 FR 11638 - Michigan Consolidated Gas Company, DTE Gas Company, DTE Gas Company; Notice of Petition

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-19

    ... Energy Regulatory Commission Michigan Consolidated Gas Company, DTE Gas Company, DTE Gas Company; Notice... Docket Nos. PR13-29-000, and PR13-30-000 (not consolidated), Michigan Consolidated Gas Company (MichCon) and DTE Gas Company (DTE Gas) filed to institute a name change to both itself from MichCon to DTE...

  1. Gas shielding apparatus

    DOEpatents

    Brandt, D.

    1985-12-31

    An apparatus is disclosed for preventing oxidation by uniformly distributing inert shielding gas over the weld area of workpieces such as pipes being welded together. The apparatus comprises a chamber and a gas introduction element. The chamber has an annular top wall, an annular bottom wall, an inner side wall and an outer side wall connecting the top and bottom walls. One side wall is a screen and the other has a portion defining an orifice. The gas introduction element has a portion which encloses the orifice and can be one or more pipes. The gas introduction element is in fluid communication with the chamber and introduces inert shielding gas into the chamber. The inert gas leaves the chamber through the screen side wall and is dispersed evenly over the weld area. 3 figs.

  2. Gas in Protoplanetary Disks

    NASA Technical Reports Server (NTRS)

    Roberge, Aki

    2008-01-01

    Gas makes up the bulk of the mass in a protoplanetary disk, but it is much more difficult to observe than the smaller dust component. The l ifetime of gas in a disk has far-reaching consequences. including lim iting the time available for giant planet formation and controlling t he migration of planetary bodies of all sizes, from Jupiters to meter-sized planetesimals. Here I will discuss what is known about the gas component of protoplanetary disks, highlighting recent results from i nfrared studies with the Spitzer Space Telescope. Exciting upcoming o pportunities for gas studies will also be discussed. In particular, the first large far-IR survey of gas tracers from young disks will be p erformed using the Herschel Space Observatory, as part of the "Gas in Protoplanetary Systems" (GASPS) Open Time Key Project.

  3. Gas in Protoplanetary Disks

    NASA Technical Reports Server (NTRS)

    Roberge, Aki

    2008-01-01

    Gas makes up the bulk of the mass in a protoplanetary disk, but it is much more difficult to observe than the smaller dust component. The lifetime of gas in a disk has far-reaching consequences, including limiting the time available for giant planet formation and controlling the migration of planetary bodies of all sizes, from Jupiters to meter-sized planetesimals. Here I will discuss what is known about the gas component of protoplanetary disks, highlighting recent results from infrared studies with the Spitzer Space Telescope. Exciting upcoming opportunities for gas studies will also be discussed. In particular, the first large far-IR survey of gas tracers from young disks will be performed using the Herschel Space Observatory, as part of the 'Gas in Protoplanetary Systems' (GASPS) Open Time Key Project.

  4. Gas stream purifier

    NASA Technical Reports Server (NTRS)

    Adam, Steven J.

    1994-01-01

    A gas stream purifier has been developed that is capable of removing corrosive acid, base, solvent, organic, inorganic, and water vapors as well as particulates from an inert mixed gas stream using only solid scrubbing agents. This small, lightweight purifier has demonstrated the ability to remove contaminants from an inert gas stream with a greater than 99 percent removal efficiency. The Gas Stream Purifier has outstanding market and sales potential in manufacturing, laboratory and science industries, medical, automotive, or any commercial industry where pollution, contamination, or gas stream purification is a concern. The purifier was developed under NASA contract NAS9-18200 Schedule A for use in the international Space Station. A patent application for the Gas Stream Purifier is currently on file with the United States Patent and Trademark Office.

  5. Gas shielding apparatus

    DOEpatents

    Brandt, Daniel

    1985-01-01

    An apparatus for preventing oxidation by uniformly distributing inert shielding gas over the weld area of workpieces such as pipes being welded together. The apparatus comprises a chamber and a gas introduction element. The chamber has an annular top wall, an annular bottom wall, an inner side wall and an outer side wall connecting the top and bottom walls. One side wall is a screen and the other has a portion defining an orifice. The gas introduction element has a portion which encloses the orifice and can be one or more pipes. The gas introduction element is in fluid communication with the chamber and introduces inert shielding gas into the chamber. The inert gas leaves the chamber through the screen side wall and is dispersed evenly over the weld area.

  6. GAS METERING PUMP

    DOEpatents

    George, C.M.

    1957-12-31

    A liquid piston gas pump is described, capable of pumping minute amounts of gas in accurately measurable quantities. The pump consists of a flanged cylindrical regulating chamber and a mercury filled bellows. Sealed to the ABSTRACTS regulating chamber is a value and having a gas inlet and outlet, the inlet being connected by a helical channel to the bellows. A gravity check valve is in the gas outlet, so the gas passes through the inlet and the helical channel to the bellows where the pumping action as well as the metering is accomplished by the actuation of the mercury filled bellows. The gas then flows through the check valve and outlet to any associated apparatus.

  7. Hydrogen rich gas generator

    NASA Technical Reports Server (NTRS)

    Houseman, J. (Inventor)

    1976-01-01

    A process and apparatus is described for producing a hydrogen rich gas by introducing a liquid hydrocarbon fuel in the form of a spray into a partial oxidation region and mixing with a mixture of steam and air that is preheated by indirect heat exchange with the formed hydrogen rich gas, igniting the hydrocarbon fuel spray mixed with the preheated mixture of steam and air within the partial oxidation region to form a hydrogen rich gas.

  8. Pulsed gas laser

    DOEpatents

    Anderson, Louis W.; Fitzsimmons, William A.

    1978-01-01

    A pulsed gas laser is constituted by Blumlein circuits wherein space metal plates function both as capacitors and transmission lines coupling high frequency oscillations to a gas filled laser tube. The tube itself is formed by spaced metal side walls which function as connections to the electrodes to provide for a high frequency, high voltage discharge in the tube to cause the gas to lase. Also shown is a spark gap switch having structural features permitting a long life.

  9. Valve for gas centrifuges

    DOEpatents

    Hahs, Charles A.; Burbage, Charles H.

    1984-01-01

    The invention is a pneumatically operated valve assembly for simultaneously (1) closing gas-transfer lines connected to a gas centrifuge or the like and (2) establishing a recycle path between two of the lines so closed. The valve assembly is especially designed to be compact, fast-acting, reliable, and comparatively inexpensive. It provides large reductions in capital costs for gas-centrifuge cascades.

  10. Multiple complementary gas distribution assemblies

    DOEpatents

    Ng, Tuoh-Bin; Melnik, Yuriy; Pang, Lily L; Tuncel, Eda; Nguyen, Son T; Chen, Lu

    2016-04-05

    In one embodiment, an apparatus includes a first gas distribution assembly that includes a first gas passage for introducing a first process gas into a second gas passage that introduces the first process gas into a processing chamber and a second gas distribution assembly that includes a third gas passage for introducing a second process gas into a fourth gas passage that introduces the second process gas into the processing chamber. The first and second gas distribution assemblies are each adapted to be coupled to at least one chamber wall of the processing chamber. The first gas passage is shaped as a first ring positioned within the processing chamber above the second gas passage that is shaped as a second ring positioned within the processing chamber. The gas distribution assemblies may be designed to have complementary characteristic radial film growth rate profiles.

  11. Natural gas annual 1997

    SciTech Connect

    1998-10-01

    The Natural Gas Annual provides information on the supply and disposition of natural gas to a wide audience including industry, consumers, Federal and State agencies, and educational institutions. The 1997 data are presented in a sequence that follows natural gas (including supplemental supplies) from its production to its end use. This is followed by tables summarizing natural gas supply and disposition from 1993 to 1997 for each Census Division and each State. Annual historical data are shown at the national level. 27 figs., 109 tabs.

  12. Gas-Recovery System

    DOEpatents

    Heckman, R. A.

    1971-12-14

    Nuclear explosions have been proposed as a means for recovering gas from underground gas-bearing rock formations. In present practice, the nuclear device is positioned at the end of a long pipe which is subsequently filled with grout or concrete. After the device is exploded, the grout is drilled through to provide a flow path for the released gas to the ground surface. As settled grout is brittle, often the compressive shock of the explosion fractures the grout and deforms the pipe so that it may not be removed nor reused. In addition, the pipe is sometimes pinched off completely and the gas flow is totally obstructed. (2 claims)

  13. Polyport atmospheric gas sampler

    DOEpatents

    Guggenheim, S. Frederic

    1995-01-01

    An atmospheric gas sampler with a multi-port valve which allows for multi, sequential sampling of air through a plurality of gas sampling tubes mounted in corresponding gas inlet ports. The gas sampler comprises a flow-through housing which defines a sampling chamber and includes a gas outlet port to accommodate a flow of gases through the housing. An apertured sample support plate defining the inlet ports extends across and encloses the sampling chamber and supports gas sampling tubes which depend into the sampling chamber and are secured across each of the inlet ports of the sample support plate in a flow-through relation to the flow of gases through the housing during sampling operations. A normally closed stopper means mounted on the sample support plate and operatively associated with each of the inlet ports blocks the flow of gases through the respective gas sampling tubes. A camming mechanism mounted on the sample support plate is adapted to rotate under and selectively lift open the stopper spring to accommodate a predetermined flow of gas through the respective gas sampling tubes when air is drawn from the housing through the outlet port.

  14. Gas venting system

    DOEpatents

    Khan, Amjad; Dreier, Ken Wayne; Moulthrop, Lawrence Clinton; White, Erik James

    2010-06-29

    A system to vent a moist gas stream is disclosed. The system includes an enclosure and an electrochemical cell disposed within the enclosure, the electrochemical cell productive of the moist gas stream. A first vent is in fluid communication with the electrochemical cell for venting the moist gas stream to an exterior of the enclosure, and a second vent is in fluid communication with an interior of the enclosure and in thermal communication with the first vent for discharging heated air to the exterior of the enclosure. At least a portion of the discharging heated air is for preventing freezing of the moist gas stream within the first vent.

  15. Gas hydrate and humans

    USGS Publications Warehouse

    Kvenvolden, K.A.

    2000-01-01

    The potential effects of naturally occurring gas hydrate on humans are not understood with certainty, but enough information has been acquired over the past 30 years to make preliminary assessments possible. Three major issues are gas hydrate as (1) a potential energy resource, (2) a factor in global climate change, and (3) a submarine geohazard. The methane content is estimated to be between 1015 to 1017 m3 at STP and the worldwide distribution in outer continental margins of oceans and in polar regions are significant features of gas hydrate. However, its immediate development as an energy resource is not likely because there are various geological constraints and difficult technological problems that must be solved before economic recovery of methane from hydrate can be achieved. The role of gas hydrate in global climate change is uncertain. For hydrate methane to be an effective greenhouse gas, it must reach the atmosphere. Yet there are many obstacles to the transfer of methane from hydrate to the atmosphere. Rates of gas hydrate dissociation and the integrated rates of release and destruction of the methane in the geo/hydro/atmosphere are not adequately understood. Gas hydrate as a submarine geohazard, however, is of immediate and increasing importance to humans as our industrial society moves to exploit seabed resources at ever-greater depths in the waters of our coastal oceans. Human activities and installations in regions of gas-hydrate occurrence must take into account the presence of gas hydrate and deal with the consequences of its presence.

  16. Portable Gas Analyzer

    NASA Technical Reports Server (NTRS)

    1986-01-01

    The Michromonitor M500 universal gas analyzer contains a series of miniature modules, each of which is a complete gas chromatograph, an instrument which separates a gaseous mixture into its components and measures the concentrations of each gas in the mixture. The system is manufactured by Microsensor Technology, and is used for environmental analysis, monitoring for gas leaks and chemical spills, compliance with pollution laws, etc. The technology is based on a Viking attempt to detect life on Mars. Ames/Stanford miniaturized the system and NIOSH funded further development. Three Stanford researchers commercialized the technology, which can be operated by unskilled personnel.

  17. Waste gas storage

    NASA Technical Reports Server (NTRS)

    Vickers, Brian D. (Inventor)

    1994-01-01

    Method for storing a waste gas mixture comprised of nitrogen, oxygen, carbon dioxide, and inert gases, the gas mixture containing corrosive contaminants including inorganic acids and bases and organic solvents, and derived from space station operations. The gas mixture is stored under pressure in a vessel formed of a filament wound composite overwrap on a metal liner, the metal liner being pre-stressed in compression by the overwrap, thereby avoiding any tensile stress in the liner, and preventing stress corrosion cracking of the liner during gas mixture storage.

  18. Water gas furnace

    SciTech Connect

    Gallaro, C.

    1985-12-03

    A water gas furnace comprising an outer container to provide a housing in which coke is placed into its lower part. A water container is placed within the housing. The coke is ignited and heats the water in the container converting it into steam. The steam is ejected into the coke, which together with air, produces water gas. Preferably, pumice stones are placed above the coke. The water gas is accepted into the pores of the pumice stones, where the heated pumice stones ignite the water gas, producing heat. The heat is extracted by a heat exchanger provided about the housing.

  19. Gas-recovery system

    DOEpatents

    Heckman, R.A.

    1971-12-14

    Nuclear explosions have been proposed as a means for recovering gas from underground gas-bearing rock formations. In present practice, the nuclear device is positioned at the end of a long pipe which is subsequently filled with grout or concrete. After the device is exploded, the grout is drilled through to provide a flow path for the released gas to the ground surface. As settled grout is brittle, often the compressive shock of the explosion fractures the grout and deforms the pipe so that it may not be removed nor reused. In addition, the pipe is sometimes pinched off completely and the gas flow is totally obstructed. (2 claims)

  20. Gas utilization technologies

    SciTech Connect

    Biljetina, R.

    1994-09-01

    One of the constant challenges facing the research community is the identification of technology needs 5 to 15 years from now. A look back into history indicates that the forces driving natural gas research have changed from decade to decade. In the 1970s research was driven by concerns for adequate supply; in the 1980s research was aimed at creating new markets for natural gas. What then are the driving forces for the 1990s? Recent reports from the natural gas industry have helped define a new direction driven primarily by market demand for natural gas. A study prepared by the Interstate Natural Gas Association of America Foundation entitled ``Survey of Natural Research, Development, and Demonstration RD&D Priorities`` indicated that in the 1990s the highest research priority should be for natural gas utilization and that technology development efforts should not only address efficiency and cost, but environmental and regulatory issues as well. This study and others, such as the report by the American Gas Association (A.G.A.) entitled ``Strategic Vision for Natural Gas Through the Year 2000,`` clearly identify the market sectors driving today`s technology development needs. The biggest driver is the power generation market followed by the industrial, transportation, appliance, and gas cooling markets. This is best illustrated by the GRI 1994 Baseline Projection on market growth in various sectors between the year 1992 and 2010. This paper highlights some of the recent technology developments in each one of these sectors.

  1. Residual gas pressures in sealed fused silica glass ampoules

    NASA Astrophysics Data System (ADS)

    Palosz, Witold; Wiedemeier, Heribert

    1993-07-01

    The residual gas pressures in sealed and annealed ampoules made from silica glass have been determined using different methods including a McLeod gauge. It has been found that the gas build-up in the ampoule is mainly the result of the ampoule heat treatment; the amount of gas released and trapped during sealing the ampoule under vacuum is much less. The pressures in the ampoules after heat treatment range from a few mTorr to a few Torr, depending on the silica glass and on the outgassing and annealing procedures.

  2. Passive drainage and biofiltration of landfill gas: Australian field trial

    SciTech Connect

    Dever, S.A. . E-mail: stuart_dever@ghd.com.au; Swarbrick, G.E. . E-mail: g.swarbrick@unsw.edu.au; Stuetz, R.M. . E-mail: r.stuetz@unsw.edu.au

    2007-07-01

    In Australia a significant number of landfill waste disposal sites do not incorporate measures for the collection and treatment of landfill gas. This includes many old/former landfill sites, rural landfill sites, non-putrescible solid waste and inert waste landfill sites, where landfill gas generation is low and it is not commercially viable to extract and beneficially utilize the landfill gas. Previous research has demonstrated that biofiltration has the potential to degrade methane in landfill gas, however, the microbial processes can be affected by many local conditions and factors including moisture content, temperature, nutrient supply, including the availability of oxygen and methane, and the movement of gas (oxygen and methane) to/from the micro-organisms. A field scale trial is being undertaken at a landfill site in Sydney, Australia, to investigate passive drainage and biofiltration of landfill gas as a means of managing landfill gas emissions at low to moderate gas generation landfill sites. The design and construction of the trial is described and the experimental results will provide in-depth knowledge on the application of passive gas drainage and landfill gas biofiltration under Sydney (Australian) conditions, including the performance of recycled materials for the management of landfill gas emissions.

  3. Low-Quality Natural Gas Sulfur Removal/Recovery System

    SciTech Connect

    Lokhandwala, K.A.; Ringer, M.; Wijams, H.; Baker, R.W.

    1997-10-01

    Natural gas provides more than one-fifth of all the primary energy used in the United States. Much raw gas is `subquality`, that is, it exceeds the pipeline specifications for nitrogen, carbon dioxide, and/or hydrogen sulfide content, and much of this low-quality natural gas cannot be produced economically with present processing technology. Against this background, a number of industry-wide trends are affecting the natural gas industry. Despite the current low price of natural gas, long-term demand is expected to outstrip supply, requiring new gas fields to be developed. Several important consequences will result. First, gas fields not being used because of low-quality products will have to be tapped. In the future, the proportion of the gas supply that must be treated to remove impurities prior to delivery to the pipeline will increase substantially. The extent of treatment required to bring the gas up to specification will also increase. Gas Research Institute studies have shown that a substantial capital investment in facilities is likely to occur over the next decade. The estimated overall investment for all gas processing facilities up to the year 2000 alone is approximates $1.2 Billion, of which acid gas removal and sulfur recovery are a significant part in terms of invested capital. This large market size and the known shortcomings of conventional processing techniques will encourage development and commercialization of newer technologies such as membrane processes. Second, much of today`s gas production is from large, readily accessible fields. As new reserves are exploited, more gas will be produced from smaller fields in remote or offshore locations. The result is an increasing need for technology able to treat small-scale gas streams.

  4. Improved polyacrylamide treatments for water control in producing wells

    SciTech Connect

    Zaltoun, A.; Kohler, N. ); Guerrini, Y. )

    1991-07-01

    This paper reports on two polyacrylamide processes for water control in producing wells which improve the efficiency of conventional polyacrylamide treatment without inducing any risk of well plugging by crosslinkers. Treatment of a gas-storage well strongly decreased water production without any adverse effect on gas injection or production for at least 3 years.

  5. Underground Coal Thermal Treatment

    SciTech Connect

    Smith, P.; Deo, M.; Eddings, E.; Sarofim, A.; Gueishen, K.; Hradisky, M.; Kelly, K.; Mandalaparty, P.; Zhang, H.

    2012-01-11

    The long-term objective of this work is to develop a transformational energy production technology by insitu thermal treatment of a coal seam for the production of substitute natural gas (SNG) while leaving much of the coal's carbon in the ground. This process converts coal to a high-efficiency, low-GHG emitting gas fuel. It holds the potential of providing environmentally acceptable access to previously unusable coal resources. This topical report discusses the development of experimental capabilities, the collection of available data, and the development of simulation tools to obtain process thermo-chemical and geo-thermal parameters in preparation for the eventual demonstration in a coal seam. It also includes experimental and modeling studies of CO2 sequestration.

  6. Automatic gas burner block for thermal units

    SciTech Connect

    Kryzhanovskii, K.S.; Senatov, V.I.

    1987-01-01

    The authors describe a new computerized control system and gas burner configuration for natural gas furnaces used for the heat treatment of ceramics and porcelain which is designed to control and monitor combustion and temperature regimes in the furnace and optimize fuel efficiency. The system permits simultaneous operation and thermal load control of up to 12 burners, automatic maintenance of the desired fuel-air ratio over the entire temperature range, and protection of the furnace against overload by the use of a fuel cutoff switch. Specifications on productivity and efficiency and results of performance evaluations are listed.

  7. The photon gas formulation of thermal radiation

    NASA Technical Reports Server (NTRS)

    Ried, R. C., Jr.

    1975-01-01

    A statistical consideration of the energy, the linear momentum, and the angular momentum of the photons that make up a thermal radiation field was presented. A general nonequilibrium statistical thermodynamics approach toward a macroscopic description of thermal radiation transport was developed and then applied to the restricted equilibrium statistical thermostatics derivation of the energy, linear momentum, and intrinsic angular momentum equations for an isotropic photon gas. A brief treatment of a nonisotropic photon gas, as an example of the results produced by the nonequilibrium statistical thermodynamics approach, was given. The relativistic variation of temperature and the invariance of entropy were illustrated.

  8. Gas sensing in nematodes.

    PubMed

    Carrillo, M A; Hallem, E A

    2015-01-01

    Nearly all animals are capable of sensing changes in environmental oxygen (O2) and carbon dioxide (CO2) levels, which can signal the presence of food, pathogens, conspecifics, predators, or hosts. The free-living nematode Caenorhabditis elegans is a powerful model system for the study of gas sensing. C. elegans detects changes in O2 and CO2 levels and integrates information about ambient gas levels with other internal and external cues to generate context-appropriate behavioral responses. Due to its small nervous system and amenability to genetic and genomic analyses, the functional properties of its gas-sensing microcircuits can be dissected with single-cell resolution, and signaling molecules and natural genetic variations that modulate gas responses can be identified. Here, we discuss the neural basis of gas sensing in C. elegans, and highlight changes in gas-evoked behaviors in the context of other sensory cues and natural genetic variations. We also discuss gas sensing in other free-living nematodes and parasitic nematodes, focusing on how gas-sensing behavior has evolved to mediate species-specific behavioral requirements. PMID:24906953

  9. Gas injected vacuum switch

    DOEpatents

    Hardin, K. Dan

    1977-01-01

    The disclosure relates to a gas injected vacuum switch comprising a housing having an interior chamber, a conduit for evacuating the interior chamber, within the chamber an anode and a cathode spaced from the anode, and a detonator for injecting electrically conductive gas into the chamber between the anode and the cathode to provide a current path therebetween.

  10. Standard gas hardware

    NASA Technical Reports Server (NTRS)

    Spencer, Stan

    1995-01-01

    The Sierra College Space Technology Program is currently building their third GAS payload in addition to a small satellite. The project is supported by an ARPA/TRP grant. One aspect of the grant is the design of standard hardware for Get Away Specials (GAS) payloads. A standard structure has been designed and work is progressing on a standard battery box and computer.

  11. Fission gas detection system

    DOEpatents

    Colburn, Richard P.

    1985-01-01

    A device for collecting fission gas released by a failed fuel rod which device uses a filter to pass coolant but which filter blocks fission gas bubbles which cannot pass through the filter due to the surface tension of the bubble.

  12. Gas Detectors, Volume 1.

    ERIC Educational Resources Information Center

    Defense Documentation Center, Alexandria, VA.

    The report contains annotated references on gas detectors compiled from the Defense Documentation Center's data bank. The range of the topics deals with detection of toxic propellants, odors, gas leaks, oxygen, etc. Included with the bibliographic reference are the corporate author-monitoring agency, subject, and title indexes. (Author/JR)

  13. Small Gas Engine Repair.

    ERIC Educational Resources Information Center

    Connecticut State Dept. of Education, Hartford. Div. of Vocational-Technical Schools.

    Instructional materials are provided for a small gas engine course. A list of objectives appears first, followed by a list of internal parts and skills/competencies related to those parts for engine work, ignition and electrical systems, fuel system, crankcase lubrication system, arc welding skills, and gas welding skills. Outlines are provided…

  14. Gas pump with movable gas pumping panels

    DOEpatents

    Osher, J.L.

    Apparatus for pumping gas continuously a plurality of articulated panels of getter material, each of which absorbs gases on one side while another of its sides is simultaneously reactivated in a zone isolated by the panels themselves from a working space being pumped.

  15. Fastrac Gas Generator Testing

    NASA Technical Reports Server (NTRS)

    Nesman, Tomas E.; Dennis, Jay

    2001-01-01

    A rocket engine gas generator component development test was recently conducted at the Marshall Space Flight Center. This gas generator is intended to power a rocket engine turbopump by the combustion of Lox and RP-1. The testing demonstrated design requirements for start sequence, wall compatibility, performance, and stable combustion. During testing the gas generator injector was modified to improve distribution of outer wall coolant and the igniter boss was modified to investigate the use of a pyrotechnic igniter. Expected chamber pressure oscillations at longitudinal acoustic mode were measured for three different chamber lengths tested. High amplitude discrete oscillations resulted in the chamber-alone configurations when chamber acoustic modes coupled with feed-system acoustics modes. For the full gas generator configuration, which included a turbine inlet manifold, high amplitude oscillations occurred only at off-design very low power levels. This testing led to a successful gas generator design for the Fastrac 60,000 lb thrust engine.

  16. Fastrac Gas Generator Testing

    NASA Technical Reports Server (NTRS)

    Nesman, Tomas E.; Dennis, Jay

    1999-01-01

    A rocket engine gas generator component development test was recently conducted at the Marshall Space Flight Center. This gas generator was intended to power a rocket engine turbopump by the combustion of Lox and RP-1. The testing demonstrated design requirements for start sequence, wall compatibility, performance, and stable combustion. During testing the gas generator injector was modified to improve distribution of outer wall coolant and the igniter boss was modified to investigate the use of a pyrotechnic igniter, Expected chamber pressure oscillations at longitudinal acoustic modes were measured for three different chamber lengths tested. High amplitude discrete oscillations occurred in the chamber-alone configurations when chamber acoustic modes coupled with feed-system acoustics modes. For the full gas generator configuration, which included the turbine inlet manifold simulator, high amplitude oscillations occurred only at off-design very low power levels. This testing led to a successful gas generator design for the Fastrac 60,000 lb thrust engine.

  17. Supersonic gas compressor

    SciTech Connect

    Lawlor, Shawn P.; Novaresi, Mark A.; Cornelius, Charles C.

    2007-11-13

    A gas compressor based on the use of a driven rotor having a compression ramp traveling at a local supersonic inlet velocity (based on the combination of inlet gas velocity and tangential speed of the ramp) which compresses inlet gas against a stationary sidewall. In using this method to compress inlet gas, the supersonic compressor efficiently achieves high compression ratios while utilizing a compact, stabilized gasdynamic flow path. Operated at supersonic speeds, the inlet stabilizes an oblique/normal shock system in the gasdyanamic flow path formed between the rim of the rotor, the strakes, and a stationary external housing. Part load efficiency is enhanced by the use of a pre-swirl compressor, and using a bypass stream to bleed a portion of the intermediate pressure gas after passing through the pre-swirl compressor back to the inlet of the pre-swirl compressor. Inlet guide vanes to the compression ramp enhance overall efficiency.

  18. HIGH PRESSURE GAS REGULATOR

    DOEpatents

    Ramage, R.W.

    1962-05-01

    A gas regulator operating on the piston and feedback principle is described. The device is particularly suitable for the delicate regulation of high pressure, i.e., 10,000 psi and above, gas sources, as well as being perfectly adaptable for use on gas supplies as low as 50 psi. The piston is adjustably connected to a needle valve and the movement of the piston regulates the flow of gas from the needle valve. The gas output is obtained from the needle valve. Output pressure is sampled by a piston feedback means which, in turn, regulates the movement of the main piston. When the output is other than the desired value, the feedback system initiates movement of the main piston to allow the output pressure to be corrected or to remain constant. (AEC)

  19. Thermoacoustic natural gas liquefier

    SciTech Connect

    Swift, G.; Gardner, D.; Hayden, M.; Radebaugh, R.; Wollan, J.

    1996-07-01

    This is the final report of a two-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). This project sought to develop a natural-gas-powered natural-gas liquefier that has absolutely no moving parts and requires no electrical power. It should have high efficiency, remarkable reliability, and low cost. The thermoacoustic natural-gas liquefier (TANGL) is based on our recent invention of the first no-moving-parts cryogenic refrigerator. In short, our invention uses acoustic phenomena to produce refrigeration from heat, with no moving parts. The required apparatus comprises nothing more than heat exchangers and pipes, made of common materials, without exacting tolerances. Its initial experimental success in a small size lead us to propose a more ambitious application: large-energy liquefaction of natural gas, using combustion of natural gas as the energy source. TANGL was designed to be maintenance-free, inexpensive, portable, and environmentally benign.

  20. Eastern Gas Shales Project

    SciTech Connect

    Koen, A.D.

    1981-05-01

    The Eastern Gas Shales Project (EGSP), the DOE study to obtain reliable estimates of economically recoverable gas from shale formations in the Appalachian basin, has determined that between 20 and 50 TCF of gas can be recovered from the region. The EGSP final report states that the expected (mean) total economically recoverable gas is 20.2 TCF, with a standard deviation of 1.6 TCF, conditional on the use of shooting technology on 160-acre well spacing. If shooting technology is used and 160-acre well spacing maintained a 95% probability exists that the total recoverable gas from Appalachian basin Devonian shale is between 17.06 and 23.34 TCF.

  1. Exhaust gas recirculation system

    SciTech Connect

    Minoura, M.; Yorioka, K.

    1980-11-18

    An exhaust gas recirculation system for cleaning exhaust gas from an internal combustion engine is provided in which a variable constriction is provided between an intake pipe and a pressure control valve in operative connection to a throttle valve in the carburetor and the pressure differential across said variable constriction is maintained constant to keep off any influence of the exhaust gas pressure while the ratio of the exhaust gas flow rate to the air intake into the engine is varied in correspondence to the intake pipe negative pressure. This exhaust gas recirculation system can be adapted to a fuel injection type intake system as well as other intake systems provided with an air valve for regulating air intake or having no venturi constriction such as employed in an su type carburetor.

  2. Residual gas analyzer calibration

    NASA Technical Reports Server (NTRS)

    Lilienkamp, R. H.

    1972-01-01

    A technique which employs known gas mixtures to calibrate the residual gas analyzer (RGA) is described. The mass spectra from the RGA are recorded for each gas mixture. This mass spectra data and the mixture composition data each form a matrix. From the two matrices the calibration matrix may be computed. The matrix mathematics requires the number of calibration gas mixtures be equal to or greater than the number of gases included in the calibration. This technique was evaluated using a mathematical model of an RGA to generate the mass spectra. This model included shot noise errors in the mass spectra. Errors in the gas concentrations were also included in the valuation. The effects of these errors was studied by varying their magnitudes and comparing the resulting calibrations. Several methods of evaluating an actual calibration are presented. The effects of the number of gases in then, the composition of the calibration mixture, and the number of mixtures used are discussed.

  3. Gas Storage Technology Consortium

    SciTech Connect

    Joel Morrison

    2005-09-14

    Gas storage is a critical element in the natural gas industry. Producers, transmission and distribution companies, marketers, and end users all benefit directly from the load balancing function of storage. The unbundling process has fundamentally changed the way storage is used and valued. As an unbundled service, the value of storage is being recovered at rates that reflect its value. Moreover, the marketplace has differentiated between various types of storage services, and has increasingly rewarded flexibility, safety, and reliability. The size of the natural gas market has increased and is projected to continue to increase towards 30 trillion cubic feet (TCF) over the next 10 to 15 years. Much of this increase is projected to come from electric generation, particularly peaking units. Gas storage, particularly the flexible services that are most suited to electric loads, is critical in meeting the needs of these new markets. In order to address the gas storage needs of the natural gas industry, an industry driven consortium was created--the Gas Storage Technology Consortium (GSTC). The objective of the GSTC is to provide a means to accomplish industry-driven research and development designed to enhance operational flexibility and deliverability of the Nation's gas storage system, and provide a cost effective, safe, and reliable supply of natural gas to meet domestic demand. This report addresses the activities for the quarterly period of April 1, 2005 through June 30, 2005. During this time period efforts were directed toward (1) GSTC administration changes, (2) participating in the American Gas Association Operations Conference and Biennial Exhibition, (3) issuing a Request for Proposals (RFP) for proposal solicitation for funding, and (4) organizing the proposal selection meeting.

  4. Determination of xanomeline (LY246708 tartrate), an investigational agent for the treatment of Alzheimer's disease, in rat and monkey plasma by capillary gas chromatography with nitrogen-phosphorus detection.

    PubMed

    Brown, T J; Shipley, L A

    1995-03-24

    A GC method is described for the determination of xanomeline (LY246708 tartrate) and selected metabolites in rat and monkey plasma. The analytes, including an internal standard, were extracted from plasma at basic pH with hexane. The organic extract was evaporated to dryness and the residue was reconstituted in hexane. The analytes were separated from metabolites and endogenous substances using a DB1701 capillary column. The analytes were detected using nitrogen-phosphorus detection (NPD). The limit of quantitation was determined to be 8 ng/ml, and the response was linear from 8 to 800 ng/ml. The method has been successfully applied to rat and monkey samples pursuant to the development of xanomeline as an agent for the symptomatic treatment of Alzheimer's disease.

  5. Evolution of gas saturation and relative permeability during gas production from hydrate-bearing sediments: Gas invasion vs. gas nucleation

    NASA Astrophysics Data System (ADS)

    Jang, Jaewon; Santamarina, J. Carlos

    2014-01-01

    Capillarity and both gas and water permeabilities change as a function of gas saturation. Typical trends established in the discipline of unsaturated soil behavior are used when simulating gas production from hydrate-bearing sediments. However, the evolution of gas saturation and water drainage in gas invasion (i.e., classical soil behavior) and gas nucleation (i.e., gas production) is inherently different: micromodel experimental results show that gas invasion forms a continuous flow path while gas nucleation forms isolated gas clusters. Complementary simulations conducted using tube networks explore the implications of the two different desaturation processes. In spite of their distinct morphological differences in fluid displacement, numerical results show that the computed capillarity-saturation curves are very similar in gas invasion and nucleation (the gas-water interface confronts similar pore throat size distribution in both cases); the relative water permeability trends are similar (the mean free path for water flow is not affected by the topology of the gas phase); and the relative gas permeability is slightly lower in nucleation (delayed percolation of initially isolated gas-filled pores that do not contribute to gas conductivity). Models developed for unsaturated sediments can be used for reservoir simulation in the context of gas production from hydrate-bearing sediments, with minor adjustments to accommodate a lower gas invasion pressure Po and a higher gas percolation threshold.

  6. 75 FR 13524 - Northern Natural Gas Company, Southern Natural Gas Company, Florida Gas Transmission Company, LLC...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ... Energy Regulatory Commission Northern Natural Gas Company, Southern Natural Gas Company, Florida Gas Transmission Company, LLC, Transcontinental Gas Pipe Line Company, LLC, Enterprise Field Services, LLC; Notice of Application March 16, 2010. Take notice that on March 5, 2010, Northern Natural Gas...

  7. Natural gas purchases

    SciTech Connect

    Grenier, E.J. Jr.

    1995-09-01

    In the 1970`s gas and boilers were like oil and water as far as policy makers were concerned, culminating in the Powerplant and Industrial Fuel Use Act (perhaps a more appropriate title would have been the Fuel Non-Use Act or the Gas Non-Use Act). But now, the last two Administrations have made gas the centerpiece of their energy and environmental strategies, including promotion of gas use for boilers and electric generation. The FERC`s Order 636 almost completes the Commission`s restructuring of the gas industry that began with Order 380 (eliminating commodity minimum bills) and progressed sharply with Orders 436 and 500. It is Order 636 that has transformed the interstate pipeline business into a transportation business, with the pipelines virtually out of the merchant business altogether because the Commission is not resting on its laurels after completing implementation of Order 636. Rather, it is exploring new ways to expand the growing competitive market for gas, including the possibility of using market-based rates for interstate pipeline transportation services. Methods for the procurement of natural gas supplies are discussed.

  8. Incontinence Treatment: Newer Treatment Options

    MedlinePlus

    ... Incontinence Managing Incontinence: A Survey The Patient's Perspective Barriers on Diagnosis and Treatment Personal Stories Contact Us ... Incontinence Managing Incontinence: A Survey The Patient's Perspective Barriers on Diagnosis and Treatment Personal Stories Contact Us ...

  9. Gas Storage Technology Consortium

    SciTech Connect

    Joel L. Morrison; Sharon L. Elder

    2007-03-31

    Gas storage is a critical element in the natural gas industry. Producers, transmission and distribution companies, marketers, and end users all benefit directly from the load balancing function of storage. The unbundling process has fundamentally changed the way storage is used and valued. As an unbundled service, the value of storage is being recovered at rates that reflect its value. Moreover, the marketplace has differentiated between various types of storage services and has increasingly rewarded flexibility, safety, and reliability. The size of the natural gas market has increased and is projected to continue to increase towards 30 trillion cubic feet (TCF) over the next 10 to 15 years. Much of this increase is projected to come from electric generation, particularly peaking units. Gas storage, particularly the flexible services that are most suited to electric loads, is crucial in meeting the needs of these new markets. To address the gas storage needs of the natural gas industry, an industry-driven consortium was created - the Gas Storage Technology Consortium (GSTC). The objective of the GSTC is to provide a means to accomplish industry-driven research and development designed to enhance the operational flexibility and deliverability of the nation's gas storage system, and provide a cost-effective, safe, and reliable supply of natural gas to meet domestic demand. This report addresses the activities for the quarterly period of January1, 2007 through March 31, 2007. Key activities during this time period included: {lg_bullet} Drafting and distributing the 2007 RFP; {lg_bullet} Identifying and securing a meeting site for the GSTC 2007 Spring Proposal Meeting; {lg_bullet} Scheduling and participating in two (2) project mentoring conference calls; {lg_bullet} Conducting elections for four Executive Council seats; {lg_bullet} Collecting and compiling the 2005 GSTC Final Project Reports; and {lg_bullet} Outreach and communications.

  10. Gas Storage Technology Consortium

    SciTech Connect

    Joel L. Morrison; Sharon L. Elder

    2006-07-06

    Gas storage is a critical element in the natural gas industry. Producers, transmission & distribution companies, marketers, and end users all benefit directly from the load balancing function of storage. The unbundling process has fundamentally changed the way storage is used and valued. As an unbundled service, the value of storage is being recovered at rates that reflect its value. Moreover, the marketplace has differentiated between various types of storage services, and has increasingly rewarded flexibility, safety, and reliability. The size of the natural gas market has increased and is projected to continue to increase towards 30 trillion cubic feet (TCF) over the next 10 to 15 years. Much of this increase is projected to come from electric generation, particularly peaking units. Gas storage, particularly the flexible services that are most suited to electric loads, is critical in meeting the needs of these new markets. In order to address the gas storage needs of the natural gas industry, an industry-driven consortium was created--the Gas Storage Technology Consortium (GSTC). The objective of the GSTC is to provide a means to accomplish industry-driven research and development designed to enhance operational flexibility and deliverability of the Nation's gas storage system, and provide a cost effective, safe, and reliable supply of natural gas to meet domestic demand. This report addresses the activities for the quarterly period of April 1 to June 30, 2006. Key activities during this time period include: (1) Develop and process subcontract agreements for the eight projects selected for cofunding at the February 2006 GSTC Meeting; (2) Compiling and distributing the three 2004 project final reports to the GSTC Full members; (3) Develop template, compile listserv, and draft first GSTC Insider online newsletter; (4) Continue membership recruitment; (5) Identify projects and finalize agenda for the fall GSTC/AGA Underground Storage Committee Technology Transfer

  11. Western Gas Sands Subprogram

    SciTech Connect

    Not Available

    1983-12-01

    The Western Gas Sands Subprogram (WGSS) is a multidisciplinary research effort within the US Department of Energy program on Unconventional Gas Recovery. The subprogram, managed by DOE's Morgantown Energy Technology Center, is directed towards the development of tight (very low permeability) lenticular gas sands in the western United States. The purpose of the subprogram is to demonstrate the feasibility of economically producing natural gas from low-permeability reservoirs. The subprogram has two broad goals: (1) to reduce the uncertainty of the reservoir production potential and (2) to improve the extraction technology. With input from the gas industry, universities, and geologic and engineering consulting firms, the WGSS was broadened to include more fundamental research and development. Consequently, for the last five years it has focused on improving diagnostic instrumentation, geophysical and engineering interpretation, and stimulation techniques. Integrated geologic studies of the three priority basins containing tight sands and selected by DOE as research targets have also been pursued as part of this new effort. To date, the following tentative conclusions have evolved: Permeability of the tight gas sands can be as much as three to four orders of magnitude lower than conventional gas deposits. Nineteen western geologic basins and trends containing significant amounts of tight gas have been identified. Gas resources in the priority geologic basins are Piceance Basin, 49 tcf., Uinta Basin, 20 tcf., and Greater Green River Basin, 136 tcf. The presence of natural micro-fractures within the production zone of a reservoir and the effective propped length of hydraulically-induced fractures are the critical parameters for successful development of tight sand resources. 8 figures.

  12. Western gas sands

    SciTech Connect

    Not Available

    1985-03-01

    The purpose of this research is to demonstrate the feasibility of economically producing natural gas from low-permeability reservoirs. Two broad research goals have been defined: (1) reducing the uncertainty of the reservoir production potential, and (2) improving the extraction technology. These goals are being pursued by conducting research and encouraging industrial efforts in developing the necessary technology, including: (1) providing fundamental research into the nature of tight, lenticular gas sands and the technologies for diagnosing and developing them: (2) developing and verifying the technology for effective gas production; and (3) promoting the transfer of research products and technology advances to the gas industry in usable forms. The focus of the research for the last several years has been improving diagnostic instrumentation for reservoir and stimulation performance evaluation, geophysical and engineering interpretation, and stimulation techniques. Integrated geologic studies of three basins containing tight lenticular sands, which were selected by DOE as priority research targets, have also been pursued as part of this new effort. To date, the following tentative conclusions have been formed: Permeability of the tight gas sands can be as much as three to four orders of magnitude lower than that of conventional gas deposits. Nineteen western geologic basins and trends containing significant volumes of tight gas have been identified. Gas resources in the priority geologic basins have been estimated - Piceance Basin 49 Tcf.; Greater Green River Basin, 136 Tcf.; Uinta Basin, 20 Tcf. Presence of natural micro-fractures within a reservoir and the effective propped length of hydraulically induced fratures are the critical parameters for successful development of tight sand resources. Stimulation technology at the present time is insufficient to efficiently recover gas from lenticular tight reservoirs. 8 figs., 3 tabs.

  13. Gas Storage Technology Consortium

    SciTech Connect

    Joel L. Morrison; Sharon L. Elder

    2006-05-10

    Gas storage is a critical element in the natural gas industry. Producers, transmission and distribution companies, marketers, and end users all benefit directly from the load balancing function of storage. The unbundling process has fundamentally changed the way storage is used and valued. As an unbundled service, the value of storage is being recovered at rates that reflect its value. Moreover, the marketplace has differentiated between various types of storage services, and has increasingly rewarded flexibility, safety, and reliability. The size of the natural gas market has increased and is projected to continue to increase towards 30 trillion cubic feet (TCF) over the next 10 to 15 years. Much of this increase is projected to come from electric generation, particularly peaking units. Gas storage, particularly the flexible services that are most suited to electric loads, is critical in meeting the needs of these new markets. In order to address the gas storage needs of the natural gas industry, an industry-driven consortium was created--the Gas Storage Technology Consortium (GSTC). The objective of the GSTC is to provide a means to accomplish industry-driven research and development designed to enhance operational flexibility and deliverability of the Nation's gas storage system, and provide a cost effective, safe, and reliable supply of natural gas to meet domestic demand. This report addresses the activities for the quarterly period of January 1, 2006 through March 31, 2006. Activities during this time period were: (1) Organize and host the 2006 Spring Meeting in San Diego, CA on February 21-22, 2006; (2) Award 8 projects for co-funding by GSTC for 2006; (3) New members recruitment; and (4) Improving communications.

  14. The Gorgon gas field

    SciTech Connect

    Clegg, L.J.; Sayers, M.J.; Tait, A.M. )

    1990-09-01

    The Gorgon gas field was discovered by West Australian Petroleum Pty Limited (WAPET) in 1980 with the 1 Gorgon well, and appraised by 1 North Gorgon in 1982 and 1 Central Gorgon in 1983. The gas field is situated on the North West Shelf of Western Australia, 65 km northwest of WAPET's Barrow Island oil field, itself 65 km offshore. The Gorgon gas field is at the southwestern end of the Rankin Platform, which contains several giant gas fields. Water depth at the Gorgon gas field is around 250 m. The top of the Triassic Mungaroo Formation reservoir sequence is at approximately 3,500 m subsea. Individual meander-belt sandstones are up to 50 m thick and occur either interbedded with interchannel claystones or stacked to form sand bodies up to 220 m thick. The Triassic sediments form a tilted horst sealed by Cretaceous Barrow Group shales. Gross gas columns and net gas pays in the 1 Gorgon, 1 Central Gorgon, and 1 North Gorgon wells are 409 and 106 m, 441 and 45 m, and 761 and 136 m, respectively. The field is 5 km wide and at least 30 km long. Gas reserves are estimated at 232 {times} 10{sup 9} m{sup 3}, of which around 17% is carbon dioxide and nitrogen. The reservoir sandstones have porosities of 15 to 20% and permeabilities from tens to thousands of millidarcys. Individual zones have flowed gas at rates of up to 1.06 million m{sup 3}/day through a 31.75 mm choke.

  15. TOPICAL REVIEW: Thermal plasmas in gas mixtures

    NASA Astrophysics Data System (ADS)

    Murphy, A. B.

    2001-10-01

    The calculation and measurement of the properties of thermal plasmas in mixtures of different gases are reviewed. The calculation of composition, thermodynamic properties and transport coefficients is described. Particular attention is given to the calculation of diffusion coefficients, which is a significant problem in mixed-gas plasmas. The combined diffusion coefficient formulation is shown to be a useful method for the treatment of diffusion. Computational fluid dynamic modelling of thermal plasmas in gas mixtures is considered, using the examples of demixing in welding arcs, the turbulent mixing of atmospheric air into a plasma jet and a plasma waste destruction process. Diagnostic techniques for mixed-gas plasmas, in particular emission spectroscopy, laser scattering and laser-induced fluorescence, are discussed.

  16. Hydrogen rich gas generator

    NASA Technical Reports Server (NTRS)

    Houseman, J.; Rupe, J. H.; Kushida, R. O. (Inventor)

    1976-01-01

    A process and apparatus is described for producing a hydrogen rich gas by injecting air and hydrocarbon fuel at one end of a cylindrically shaped chamber to form a mixture and igniting the mixture to provide hot combustion gases by partial oxidation of the hydrocarbon fuel. The combustion gases move away from the ignition region to another region where water is injected to be turned into steam by the hot combustion gases. The steam which is formed mixes with the hot gases to yield a uniform hot gas whereby a steam reforming reaction with the hydrocarbon fuel takes place to produce a hydrogen rich gas.

  17. Gas ampoule-syringe

    DOEpatents

    Gay, Don D.

    1986-01-01

    A gas ampoule for the shipment and delivery of radioactive gases. The gas ampoule having a glass tube with serum bottle stopper on one end and a plunger tip in the opposite end all fitting in a larger plastic tube threaded on each end with absorbent between the tubes, is seated onto the internal needle assembly via a bushing associated with the plunger and locked into the syringe barrel via barrel-bushing locking caps. The design practically eliminates the possibility of personnel contamination due to an inadvertent exposure of such personnel to the contained radioactive gas.

  18. Gas ampoule-syringe

    DOEpatents

    Gay, D.D.

    1985-02-02

    A gas ampoule for the shipment and delivery of radioactive gases. The gas ampoule having a glass tube with serum bottle stopper on one and a plunger tip in the opposite end all fitting in a larger plastic tube threaded on each end with absorbent between the tubes, is seated onto the internal needle assembly via a bushing associated with the plunger and locked into the syringe barrel via barrel-bushing locking caps. The design practically eliminates the possibility of personnel contamination due to an inadvertent exposure of such personnel to the contained radioactive gas.

  19. Gas only nozzle

    DOEpatents

    Bechtel, William Theodore; Fitts, David Orus; DeLeonardo, Guy Wayne

    2002-01-01

    A diffusion flame nozzle gas tip is provided to convert a dual fuel nozzle to a gas only nozzle. The nozzle tip diverts compressor discharge air from the passage feeding the diffusion nozzle air swirl vanes to a region vacated by removal of the dual fuel components, so that the diverted compressor discharge air can flow to and through effusion holes in the end cap plate of the nozzle tip. In a preferred embodiment, the nozzle gas tip defines a cavity for receiving the compressor discharge air from a peripheral passage of the nozzle for flow through the effusion openings defined in the end cap plate.

  20. Thermionic gas switch

    DOEpatents

    Hatch, George L.; Brummond, William A.; Barrus, Donald M.

    1986-01-01

    A temperature responsive thermionic gas switch having folded electron emitting surfaces. An ionizable gas is located between the emitter and an interior surface of a collector, coaxial with the emitter. In response to the temperature exceeding a predetermined level, sufficient electrons are derived from the emitter to cause the gas in the gap between the emitter and collector to become ionized, whereby a very large increase in current in the gap occurs. Due to the folded emitter surface area of the switch, increasing the "on/off" current ratio and adjusting the "on" current capacity is accomplished.

  1. Gas Phase Nanoparticle Synthesis

    NASA Astrophysics Data System (ADS)

    Granqvist, Claes; Kish, Laszlo; Marlow, William

    This book deals with gas-phase nanoparticle synthesis and is intended for researchers and research students in nanomaterials science and engineering, condensed matter physics and chemistry, and aerosol science. Gas-phase nanoparticle synthesis is instrumental to nanotechnology - a field in current focus that raises hopes for environmentally benign, resource-lean manufacturing. Nanoparticles can be produced by many physical, chemical, and even biological routes. Gas-phase synthesis is particularly interesting since one can achieve accurate manufacturing control and hence industrial viability.

  2. INTENSE ENERGETIC GAS DISCHARGE

    DOEpatents

    Luce, J.S.

    1960-03-01

    A method and apparatus for initiating and sustaining an energetic gas arc discharge are described. A hollow cathode and a hollow anode are provided. By regulating the rate of gas flow into the interior of the cathode, the arc discharge is caused to run from the inner surface of the cathode with the result that adequate space-charge neutralization is provided inside the cathode but not in the main arc volume. Thus, the gas fed to the cathode is substantially completely ionized before it leaves the cathode, with the result that an energetic arc discharge can be maintained at lower operating pressures.

  3. Gas and Shadow Swing

    NASA Astrophysics Data System (ADS)

    Tsai, Chi-Hung; Lai, Mei-Yi; Liu, Che-Wei; Huang, Shiang-Yin; Lin, Che-Yu; Yeh, Jeng-Sheng

    In our digital art, we design a folding fan as an interactive magic device. You can use it to play with gas around the world of illusions. Although gas could not be seen in our real world, we still want to interact with it in our illusions by the element of bubble shadows. Opening and swinging the folding fan can blow the bubble shadows away; closing and swinging it can break bubbles. If the magic fan touches the shadow of gas, the bubble shadows will explode and release colorful particles to surround you. Those actions are controlled and located by our circuits with Arduino board.

  4. Blood Gas Analyzers.

    PubMed

    Gonzalez, Anthony L; Waddell, Lori S

    2016-03-01

    Acid-base and respiratory disturbances are common in sick and hospitalized veterinary patients; therefore, blood gas analyzers have become integral diagnostic and monitoring tools. This article will discuss uses of blood gas analyzers, types of samples that can be used, sample collection methods, potential sources of error, and potential alternatives to blood gas analyzers and their limitations. It will also discuss the types of analyzers that are available, logistical considerations that should be taken into account when purchasing an analyzer, and the basic principles of how these analyzers work. PMID:27451046

  5. Gas pipe explorer robot

    NASA Technical Reports Server (NTRS)

    Wilcox, Brian (Inventor)

    2004-01-01

    A gas pipe explorer formed of a plurality of connecting elements, and an articulation element between the connected elements. The connected elements include drive capabilities, and the articulation element allows the connected elements to traverse gas pipes of arbitrary shapes and sizes. A sensor may sends the characteristics of the gas pipe, and the communication element may send back those sends characteristics. The communication can be wired, over a tether connecting the device to a remote end. Alternatively, the connection can be wireless, driven by either a generator or a battery.

  6. Exhaust gas purifying device

    SciTech Connect

    Sakurai, S.; Hamada, S.

    1985-04-23

    An exhaust gas purifying device for use with a diesel engine comprising a filter block disposed in an engine exhaust passage for collecting exhaust gas particulates, and a heater for incinerating the collected exhaust gas particulates. The filter block has parallel channels defined therein and separated from one another by porous partition walls, some of the channels being closed at their inlet ends with blind plugs while the other channels are closed at their outlet ends with blind plugs. The heater is supported by the blind plugs.

  7. US crude oil, natural gas, and natural gas liquids reserves

    SciTech Connect

    Not Available

    1990-10-05

    This report presents estimates of proved reserves of crude oil, natural gas, and natural gas liquids as of December 31, 1989, and production volumes for the year 1989 for the total United States and for selected states and state sub-divisions. Estimates are presented for the following four categories of natural gas: total gas (wet after lease separation), its two major components (nonassociated and associated-dissolved gas), and total dry gas (wet gas adjusted for the removal of liquids at natural gas processing plants). In addition, two components of natural gas liquids, lease condensate and natural gas plant liquids, have their reserves and production reported separately. Also included is information on indicated additional crude oil reserves and crude oil, natural gas, and lease condensate reserves in nonproducing reservoirs. 28 refs., 9 figs., 15 tabs.

  8. New Mexico Gas upgrades gas measurement

    SciTech Connect

    Not Available

    1991-12-01

    For over 40 years, the base volume of natural gas within pipe line and distribution systems was obtained by utilizing such factors as measured gas pressure, temperature and calculated compressibility ratio. This paper reports that originally, the method for obtaining base volume information required a series of steps that began with manually transcribing information recorded on meter-mounted mechanical instruments. After recorded information was received, a series of calculations had to be performed. At the time, it was the only practical way to acquire and calculate corrected-volume information. Now, a new generation of electronic instruments is capable of interfacing with computer software programs, enabling the data collection and calculation process to be replaced by electronic technology.

  9. Mixed noble gas effect on cut green peppers

    NASA Astrophysics Data System (ADS)

    Raymond, L. V.; Zhang, M.; Karangwa, E.; Chesereka, M. J.

    2013-01-01

    Increasing attempts at using gas which leads to hydrate formation as a preservative tool in fresh-cut fruits and vegetables have been reported. In this study, changes in some physical and biochemical properties of fresh-cut green peppers under compressed noble gas treatments were examined. Mixed argonkrypton and argon treatments were performed before cold storage at 5°C for 15 days. Mass loss and cell membrane permeability were found to be the lowest in mixed argon-krypton samples. Besides, a lower CO2 concentration and vitamin C loss were detected in gastreated samples compared to untreated samples (control). While the total phenol degradation was moderately reduced, the effect of the treatment on polyphenoloxidase activity was better at the beginning of the storage period. The minimum changes in quality observed in cut peppers resulted from both mixed and gas treatment alone.

  10. Gas-separation process

    DOEpatents

    Toy, Lora G.; Pinnau, Ingo; Baker, Richard W.

    1994-01-01

    A process for separating condensable organic components from gas streams. The process makes use of a membrane made from a polymer material that is glassy and that has an unusually high free volume within the polymer material.

  11. Gas particle radiator

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L.

    1987-01-01

    The performance of a new space radiator concept, the gas particle radiator (GPR), is studied. The GPR uses a gas containing submicron particles as the radiating medium contained between the radiator's emitting surface and a transparent window. For a modest volume fraction of submicron particles and gas thickness, it is found that the emissivity is determined by the window transmittance. The window must have a high transmittance in the infrared and be structurally strong enough to contain the gas-particle mixture. When the GPR is compared to a proposed titanium wall, potassium heat pipe radiator, with both radiators operating at a power level of 1.01 MW at 775 K, it is found that the GPR mass is 31 percent lower than that of the heat pipe radiator.

  12. Fluid Inclusion Gas Analysis

    DOE Data Explorer

    Dilley, Lorie

    2013-01-01

    Fluid inclusion gas analysis for wells in various geothermal areas. Analyses used in developing fluid inclusion stratigraphy for wells and defining fluids across the geothermal fields. Each sample has mass spectrum counts for 180 chemical species.

  13. Natural gas repowering experience

    SciTech Connect

    Bautista, P.J.; Fay, J.M.; Gerber, F.B.

    1995-12-31

    Gas Research Institute has led a variety of projects in the past two years with respect to repowering with natural gas. These activities, including workshops, technology evaluations, and market assessments, have indicated that a significant opportunity for repowering exists. It is obvious that the electric power industry`s restructuring and the actual implementation of environmental regulations from the Clean Air Act Amendments will have significant impact on repowering with respect to timing and ultimate size of the market. This paper summarizes the results and implications of these activities in repowering with natural gas. It first addresses the size of the potential market and discusses some of the significant issues with respect to this market potential. It then provides a perspective on technical options for repowering which are likely to be competitive in the current environment. Finally, it addresses possible actions by the gas industry and GRI to facilitate development of the repowering market.

  14. Natural gas monthly

    SciTech Connect

    1996-05-01

    This document highlights activities, events, and analyses of interest to public and private sector organizations associated with the natural gas industry. Data presented include volume and price, production, consumption, underground storage, and interstate pipeline activities.

  15. Safer Liquid Natural Gas

    NASA Technical Reports Server (NTRS)

    1976-01-01

    After the disaster of Staten Island in 1973 where 40 people were killed repairing a liquid natural gas storage tank, the New York Fire Commissioner requested NASA's help in drawing up a comprehensive plan to cover the design, construction, and operation of liquid natural gas facilities. Two programs are underway. The first transfers comprehensive risk management techniques and procedures which take the form of an instruction document that includes determining liquid-gas risks through engineering analysis and tests, controlling these risks by setting up redundant fail safe techniques, and establishing criteria calling for decisions that eliminate or accept certain risks. The second program prepares a liquid gas safety manual (the first of its kind).

  16. Gas turbine engine

    DOEpatents

    Lawlor, Shawn P.; Roberts, II, William Byron

    2016-03-08

    A gas turbine engine with a compressor rotor having compressor impulse blades that delivers gas at supersonic conditions to a stator. The stator includes a one or more aerodynamic ducts that each have a converging portion and a diverging portion for deceleration of the selected gas to subsonic conditions and to deliver a high pressure oxidant containing gas to flameholders. The flameholders may be provided as trapped vortex combustors, for combustion of a fuel to produce hot pressurized combustion gases. The hot pressurized combustion gases are choked before passing out of an aerodynamic duct to a turbine. Work is recovered in a turbine by expanding the combustion gases through impulse blades. By balancing the axial loading on compressor impulse blades and turbine impulse blades, asymmetrical thrust is minimized or avoided.

  17. High Velocity Gas Gun

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A video tape related to orbital debris research is presented. The video tape covers the process of loading a High Velocity Gas Gun and firing it into a mounted metal plate. The process is then repeated in slow motion.

  18. Great natural gas swindle

    SciTech Connect

    Karkkainen, B.

    1981-07-01

    The Citizen/Labor Energy Coalition (C/LEC) is challenging natural gas deregulation bids by oil companies, which control 70% of domestic gas production, that will double or triple costs to consumers by 1985. Price increases will affect the cost of consumer goods, food, and several basic industries as well as residential heating bills. C/LEC disagrees with the Reagan administration that decontrol is needed to encourage production because this did not happen with the incentives provided by the Natural Gas Policy Act. Conservation will not be affected either because the capital needed for conservation investment will be used for higher gas bills. With higher employment another direct result, the only beneficiaries of decontrol appear to be the producers. (DCK)

  19. Paraelectric gas flow accelerator

    NASA Technical Reports Server (NTRS)

    Sherman, Daniel M. (Inventor); Wilkinson, Stephen P. (Inventor); Roth, J. Reece (Inventor)

    2001-01-01

    A substrate is configured with first and second sets of electrodes, where the second set of electrodes is positioned asymmetrically between the first set of electrodes. When a RF voltage is applied to the electrodes sufficient to generate a discharge plasma (e.g., a one-atmosphere uniform glow discharge plasma) in the gas adjacent to the substrate, the asymmetry in the electrode configuration results in force being applied to the active species in the plasma and in turn to the neutral background gas. Depending on the relative orientation of the electrodes to the gas, the present invention can be used to accelerate or decelerate the gas. The present invention has many potential applications, including increasing or decreasing aerodynamic drag or turbulence, and controlling the flow of active and/or neutral species for such uses as flow separation, altering heat flow, plasma cleaning, sterilization, deposition, etching, or alteration in wettability, printability, and/or adhesion.

  20. Natural Gas Emergencies

    MedlinePlus

    ... by the Cass (ND) and Clay (MN) Emergency Planning Partnerships. Adapted with funding provided by Fargo Cass Public Health through the Cities Readiness Initiative (CRI) English – Natural Gas Emergencies - Last ...